Optimum Fixed Income Fund (OIFIX) N-CSRCertified annual shareholder report (management investment company)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED MANAGEMENT
INVESTMENT COMPANIES

Item 1. Reports to Stockholders

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Other than Macquarie Bank Limited ABN 46 008 583 542 (“Macquarie Bank”), any Macquarie Group entity noted in this document is not an authorized deposit-taking institution for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these other Macquarie Group entities do not represent deposits or other liabilities of Macquarie Bank. Macquarie Bank does not guarantee or otherwise provide assurance in respect of the obligations of these other Macquarie Group entities. In addition, if this document relates to an investment, (a) the investor is subject to investment risk including possible delays in repayment and loss of income and principal invested and (b) none of Macquarie Bank or any other Macquarie Group entity guarantees any particular rate of return on or the performance of the investment, nor do they guarantee repayment of capital in respect of the investment.

The Funds are governed by US laws and regulations.

Unless otherwise noted, views expressed herein are current as of March 31, 2022, and subject to change for events occurring after such date.

The Funds are not FDIC insured and are not guaranteed. It is possible to lose the principal amount invested.

Macquarie Asset Management (MAM) is the asset management division of Macquarie Group. MAM is a full-service asset manager offering a diverse range of products across public and private markets including fixed income, equities, multi-asset solutions, private credit, infrastructure, renewables, natural assets, real estate, and asset finance. The Public Investments business is a part of MAM which includes investment products and advisory services distributed and offered by and referred through affiliates which include Delaware Distributors, L.P., a registered broker/dealer and member of the Financial Industry Regulatory Authority (FINRA), and Macquarie Investment Management Business Trust (MIMBT), a Securities and Exchange Commission (SEC)-registered investment advisor. Investment advisory services are provided by a series of MIMBT. Macquarie Group refers to Macquarie Group Limited and its subsidiaries and affiliates worldwide.

All third-party marks cited are the property of their respective owners.

© 2022 Macquarie Management Holdings, Inc.

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Portfolio management review
Optimum Fixed Income Fund

March 31, 2022 (Unaudited)

Past performance does not guarantee future results.

For complete, annualized performance for Optimum Fixed Income Fund, please see the table on page 19.

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

The performance of Class A shares excludes the applicable sales charge. Both Institutional Class shares and Class A shares reflect the reinvestment of all distributions. Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index.

*Total returns for the report period presented in the table differs from the return in “Financial highlights.” The total returns presented in the above table are calculated based on the net asset value (NAV) at which shareholder transactions were processed. The total returns presented in “Financial highlights” are calculated in the same manner, but also takes into account certain adjustments that are necessary under US generally accepted accounting principles (US GAAP) required in the annual report.

Fund objective

The Fund seeks a high level of income and may also seek growth of capital.

Advisor

Delaware Management Company (DMC)

Sub-advisor

Pacific Investment Management Company LLC (PIMCO)

Market review

After a volatile 2020 calendar year, the distribution of vaccines and the easing of lockdowns helped 2021 start on a good note and an economic rebound followed, although the emergence of new variants of COVID-19 weighed on markets during the second half of 2021. The speed of the economic recovery, coupled with the volatile path of the virus, contributed to significant friction in both goods and labor markets. This contributed to elevated inflation. During the pandemic, consumers shifted away from spending on services toward purchasing goods, which drove a relative price adjustment.

Continued economic recovery defined the Fund’s fiscal year as well as increasing concerns about inflation and central bank policy in the US and globally. The US Consumer Price Index accelerated from a 2.6% year-over-year increase in March 2021 to 7.9% in February 2022. The US labor markets transitioned from robust to tight, with unemployment declining to 3.6% in March 2022 from 6% in March 2021, and labor market participation beginning its return to normal.

From the start of the Fund’s fiscal year in April through the end of 2021, markets continued to rise relatively steadily, with the S&P 500^® Index notching numerous record highs while generating a return of 21.22% for the nine months. There was an overall lack of volatility in 2021, with the S&P 500 Index's biggest loss at approximately 5%. Investors increased their focus on Treasury inflation-protected securities (TIPS) as a hedge for unknown inflation risks, with TIPS, as represented by the Bloomberg US TIPS Index, returning 7.54% for the April-December 2021 period. While the S&P 500 Index continued its strong rally, emerging markets equities had negative total returns for the 9-month period from April through December 2021. High yield spreads ended 2021 substantially tighter, while changes in investment grade spreads were more muted. US Treasury yields rose across the curve, with the 10-year yield ending 2021 at 1.51% and fixed income markets generally posting positive returns, with the Bloomberg US Aggregate Index returning 1.89% from April 1 through the end of 2021.

January 2022 was a volatile month as both risk assets and safe-haven assets generally declined. The potential for higher, longer inflation, coupled with hawkish comments from US Federal Reserve Chairman Jerome Powell, triggered a broad market selloff. In February, worries shifted from the pandemic to the impending confrontation in Ukraine. Russia invaded Ukraine during the latter half of the month, resulting in a flight to safety and losses across global equity and credit markets. Punitive sanctions against Russia led to heightened supply chain concerns. Commodity prices jumped, and West Texas Intermediate (WTI) crude oil surpassed $100 a barrel for the first time since 2014.

In late March, investor concerns eased somewhat. While the Fed raised US interest rates by 0.25 percentage points, as expected, it highlighted upside inflationary risks and revised its “dot plot” projections to reflect seven total expected rate hikes this year – in contrast to the Bank of England (BoE)’s dovish messaging that accompanied its own quarter-point rate hike. Despite the Fed’s relatively hawkish tone, US equities rose following the Fed’s announcement. The BoE noted risks to growth stemming from the Russia-Ukraine conflict. Commodities markets, including metals, energy, and agriculture, remained strained.

The 2-year Treasury yield rose from 0.16% to 2.33% during the Fund's fiscal year. The yield curve flattened dramatically, raising concerns about its inversion and the rising risk of recession. Meanwhile, primary mortgage rates escalated from 3.3% in

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Portfolio management review
Optimum Fixed Income Fund

December 2021 to 4.9% in March 2022 after about two years of being near all-time lows. The housing market, having benefited from low interest rates, limited inventory, and robust demand, showed early signs of deceleration.

Source: Bloomberg, unless noted otherwise.

Fund performance

For the fiscal year ended March 31, 2022, Optimum Fixed Income Fund underperformed its benchmark, the Bloomberg US Aggregate Index. Before fees, each of the Fund’s component parts, managed by DMC and PIMCO, outperformed the return of the benchmark. The following remarks describe factors that affected relative performance within these respective portions.

DMC

For the fiscal year ended March 31, 2022, DMC’s portion of Optimum Fixed Income Fund outperformed its benchmark, the Bloomberg US Aggregate Index, on a gross of fees basis.

Within broad fixed income, absolute returns reflected one of the asset class’s more severe negative-return periods in the past 50+ years, as interest rates rose during the period from 1.7% to 2.3% for the 10-year Treasury. DMC aimed to capitalize on the recovery, manage rising interest rate risk, and tactically – that is, realize gains from – monetize spread sector outperformance. Consequently, DMC adopted a short duration position, while reducing risk across high yield and emerging markets debt. DMC also sought to build a liquid capital reserve of Treasurys and agency residential mortgage-backed securities (RMBS) as a source of capital for a more volatile period in 2022. Some of the capital was subsequently deployed in March 2022 as spreads widened beyond long-term averages.

Against this backdrop, DMC’s short duration contributed to performance as interest rates rose, particularly in the first quarter of 2022. While DMC’s allocation to high yield declined through 2021 toward the low end of its range, the overweight benefited relative returns, as high yield outperformed all other major sectors within fixed income. DMC’s underweight to RMBS was also beneficial. Conversely, the allocation to emerging markets debt was the principal detractor from returns as spreads widened, particularly in the first quarter of 2022, on increasing Fed tightening concerns and geopolitical risks stemming from the Russian invasion of Ukraine. Lastly, DMC had a modest allocation to US-dollar-denominated Russian and Ukrainian debt, predominantly via corporate securities. The invasion and ensuing sanctions had a negative effect on these securities, detracting from performance in DMC’s portion of the Fund.

High yield corporates were the most significant contributor to excess returns in DMC’s portion of the Fund, including a tactical allocation to European securities that was deployed and monetized in March 2022. The allocation was additive as the sector outperformed Treasurys. DMC’s consistent allocation of approximately 5% to bank loans also contributed to relative performance as the sector benefited from strong investor demand in a rising rate environment.

DMC’s underweight to RMBS contributed to the performance of its portion of the Fund as spreads widened on growing concerns over an accelerated end of quantitative easing and start of quantitative tightening.

Emerging markets debt detracted from performance in DMC’s portion of the Fund. DMC’s allocation of approximately 9% at fiscal year end, though reduced from the start of the fiscal year, was detrimental to performance. The sector offered better yield and selection opportunities than developed counterparts but ultimately suffered from a shift in monetary policy and Russia’s invasion of Ukraine.

DMC’s overweight to commercial mortgage-backed securities (CMBS) modestly detracted from performance in its portion of the Fund, with spread widening in the final quarter of the fiscal year having a net negative impact on returns as DMC maintained an allocation of approximately 9% throughout the fiscal year.

Contributions from security selection reflected DMC’s focus on a diverse set of bottom-up (bond-by-bond) opportunities as market volatility increased. Specifically, its allocation to Puerto Rico securities prior to the court decision to restructure Puerto Rico bonds in default was beneficial as the outcome was positive, leading the bonds to outperform. In addition, DMC’s allocation to convertible securities issued by Spirit Airlines Inc. during the first quarter of 2022’s bout of volatility contributed to relative returns as the bonds benefited first from the Frontier Airlines bid and then from a higher bid from JetBlue Airways.

The two leading individual detractors from performance were emerging markets corporates within headline-prone jurisdictions. Specifically, DMC’s allocation to US-dollar-denominated investment grade Russian private oil company LUKOIL detracted from returns, as the modest allocation suffered in the aftermath of the Russian invasion of Ukraine as securities initially dipped below $50. DMC believes LUKOIL is likely to weather the geopolitical risk and, at these valuations, DMC continues to hold the security.

The second notable detractor from returns was US-dollar-denominated debt of Kaisa Group Holdings Ltd., a Chinese property issuer. DMC held a position of less than 0.1% in an effort to capitalize in a diversified manner on the property market disruption. As the Chinese government initially disappointed in its willingness to support the market, the issuer underperformed. DMC modestly reduced its allocation in August 2021 but continues to hold this

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modest exposure given what it views as attractive valuations relative to potential outcomes.

With a focus on agility in a period more prone to volatility and potential for higher interest rates, DMC retained a short duration position and modestly increased its allocation to investment grade securities in March 2022 as spreads widened beyond long-term averages. Although DMC increased its high yield allocation modestly, it began monetizing the returns when markets quickly reversed course. As of fiscal year end, DMC maintained an overweight to high-quality securitized credit such as CMBS, an underweight to agency RMBS, and a sub-average allocation to structural “plus sectors” such as high yield and emerging markets debt.

During the fiscal year, DMC used a variety of derivatives, including Treasury futures, primarily used to manage yield curve risk. It also used credit default swaps and currency hedges. The use of derivatives added slightly more than 0.50% to performance for DMC’s portion of the Fund for the fiscal year.

PIMCO

PIMCO’s portion of the Fund outperformed its benchmark, the Bloomberg US Aggregate Index, for the 12 months ended March 31, 2022, on a gross of fees basis.

PIMCO’s interest rate strategies detracted from performance in its portion of the Fund. An overall underweight to US duration added to PIMCO’s performance as US Treasury yields rose during the fiscal year. However, this was more than offset by the negative effect from PIMCO’s yield curve positioning, including its focus on intermediate rates as front-end and intermediate rates rose more than long-end rates. Overall, non-US interest rate strategies detracted from performance in PIMCO’s portion of the Fund, including its exposure to Italian and Canadian interest rates. Contributions from short exposure to UK interest rates partially offset this, however, as yields in these regions rose. Lastly, emerging market interest rate strategies detracted from performance in PIMCO’s portion of the Fund, including an allocation to Brazilian and Mexican local rates.

Spread sector strategies added to returns in PIMCO’s portion of the Fund during the fiscal year. Select exposure to non-agency mortgages contributed to performance as these securities benefited from continued strong fundamentals. An underweight to agency mortgage-backed securities (MBS) added to PIMCO’s performance as the sector underperformed like-duration Treasurys. PIMCO’s relative value positioning within agency MBS also added to performance. An underweight to investment grade corporate credit also helped performance in PIMCO’s portion of the Fund as the sector underperformed like-duration Treasurys. Lastly, an allocation to US TIPS contributed to PIMCO’s performance as inflation expectations rose.

Currency strategies were positive for performance in PIMCO’s portion of the Fund, including exposure to a basket of Latin American emerging market currencies that appreciated relative to the US dollar during the fiscal year.

At fiscal year end, PIMCO was neutral to modestly underweight duration, favoring US interest rates along with hedges in select regions and countries such as the UK. PIMCO also had some diversifying rate exposure in Europe, mainly Denmark and Italy.

Regarding spread strategies, PIMCO’s portion of the Fund was underweight investment grade corporate credit, maintaining diversified credit exposures with a bias toward shorter-maturity and high-quality names while de-emphasizing generic corporate credit exposure. PIMCO actively sought compelling name and sector exposure given dispersion within the credit market. Within agency MBS, PIMCO continues to seek relative value opportunities. PIMCO also continues to favor senior positions in mortgage credit given the asset’s inherent fundamental strength and deleveraging nature.

PIMCO remains tactical with currency positioning and sees the potential to find more individual foreign exchange opportunities over time. It will continue to seek opportunities from overshoots and undershoots that provide what PIMCO considers to be attractive risk-reward profiles and the ability to diversify sources of return.

PIMCO used credit default swaps, forwards, futures, interest rate swaps, options, and swaptions during the fiscal year, but these derivatives did not have a material impact on performance within its portion of the Fund during the reporting period.

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Portfolio management review
Optimum International Fund

March 31, 2022 (Unaudited)

Past performance does not guarantee future results.

For complete, annualized performance for Optimum International Fund, please see the table on page 22

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

The performance of Class A shares excludes the applicable sales charge. Both Institutional Class shares and Class A shares reflect the reinvestment of all distributions.

Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index.

Investment objective

The Fund seeks long-term growth of capital and may also seek income.

Advisor

Delaware Management Company (DMC)

Sub-advisors

Acadian Asset Management LLC (Acadian)
Baillie Gifford Overseas Limited (Baillie Gifford)

Market review

Markets were volatile during the fiscal year, rising and falling within each quarter, but largely unchanged through the first nine months of the fiscal year ended March 31, 2022. In the final quarter of the 12-month period, equities fell sharply before recovering somewhat in the final month of the period.

There were four key drivers of performance in the markets during the Fund’s fiscal year: the effects of new COVID-19 strains on economic activity, the worsening geopolitical situation on the Russia-Ukraine border, multi-decade high inflation levels, and growing concerns that central banks would be forced to tighten monetary policy to curb inflation.

The pandemic’s continued impact on the global economy was evident throughout much of the Fund’s fiscal year. The appearance of several variants, including Delta and Omicron, resulted in sharp spikes in the number of infections in the US, China, and Europe, forcing ports and factories to close worldwide. In turn, there were raw material shortages and supply-side bottlenecks. Supply chain disruptions were so severe that global auto production fell as much as 60% between April and September.

The buildup of Russian troops on the Ukraine border and the subsequent invasion in February were also impactful, as sanctions and disruptions to the European oil and natural gas supply took a toll on the economies of both Europe and Russia. The US was also affected, as evidenced by gasoline prices rising to more than $6 per gallon in some markets.

The increase in energy prices added to the unease that inflation was out of control. Rising prices were a significant concern throughout the fiscal year, as inflation – initially dismissed by the US Federal Reserve as “transitory” – rose to levels not seen in decades. With headlines blaring that consumer prices were rising at a 4% to 6% annual rate, the Fed and other central banks began to take a more hawkish stance, ending stimulus measures, raising interest rates, and curtailing asset-purchasing programs.

Although global markets sustained a modest loss during the fiscal year, in a familiar pattern, developed markets outperformed, led by a strong US market, while emerging markets lagged. Most notably, China underperformed, weighed down by the effects of new regulations on its real estate and technology sectors, and the default of China Evergrande Group, China’s second largest property developer.

Source: Bloomberg, unless noted otherwise.

Fund performance

For the fiscal year ended March 31, 2022, Optimum International Fund underperformed its benchmark, the MSCI ACWI (All Country World) Index ex USA Index (net). Acadian’s portion of the Fund outperformed the benchmark (net of fees) while Baillie Gifford’s portion of the Fund underperformed. Stock selection was a key factor in both Acadian’s and Baillie Gifford’s portions of the Fund, providing a boost to performance for the former and detracting from the latter. Country allocations, particularly to China, also played a role in both portions of the Fund, with an underweight proving beneficial in Acadian’s portion and detrimental in Baillie Gifford’s as investors’ concern with new regulations and the default of China Evergrande hurt performance.

Acadian

Acadian focuses on its disciplined, value-focused, multi-factor approach and attempts to manage the Fund with consistency,

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objectivity, and appropriate risk controls. Acadian believes that the coronavirus pandemic has created a new set of challenges for global equities and that the current situation is fluid and evolving. In these circumstances, Acadian's approach is to maintain a calm and measured perspective, mitigating human emotion. Acadian's investment process aims to invest in securities that deliver returns over the long run, and does not rely on market timing. Acadian's investment process is designed to attempt to capture alpha by exploiting behaviorally-based mispricings within and across global equity markets.

Acadian’s portion of the Fund benefited from a combination of stock selection and overweight positions in energy and materials. Throughout the entire 12-month period, but especially in the latter months as the Russia-Ukraine conflict escalated, energy and commodity prices rose, contributing to strong returns in the energy and materials sectors.

However, the surge in inflation, which stunted consumer confidence and resulted in underperformance in the consumer discretionary sector, partially offset these gains. While Acadian’s underweight of the consumer discretionary sector in its portion of the Fund was beneficial, Acadian’s exposure to the financial sector detracted from performance.

On a country basis, Acadian’s portion of the Fund also benefited from a combination of stock selection and an overweight position in Australia, and a combination of stock selection and an overweight exposure to Israel. Underweight positions in the United Kingdom and Canada reduced these gains, as did stock selection in Switzerland.

Two holdings that contributed to Acadian’s portion of the Fund were South32 Ltd. and Alibaba Group Holdings Ltd. The share price of South32, an Australian-based mining & metals company, soared on a string of positive production results across its portfolio. The shares got a further boost from favorable operating margins that were propelled by higher commodity prices.

Alibaba Group, a China-based online and mobile commerce behemoth, experienced a slump in its share price over the 12-month period, the result of intense pressure from regulatory uncertainty over the past year. Acadian did not hold Alibaba in its portion of the Fund and therefore benefited from an underweight position in the stock.

In contrast, two holdings that detracted from Acadian’s portion of the Fund were Nintendo Co. Ltd. and Koninklijke Philips NV. Nintendo’s shares tumbled after the Japanese video game company once again confronted claims that its game controllers violate data-patent rights. The share price of Koninklijke Philips declined over the fiscal period, as the unprecedented scale of global supply-chain disruptions impaired operations. Ongoing product recalls, including Philips’ Respironics most recent recall of select ventilators, underscored product safety and quality management risks, resulting in a costly repair and replacement program, and accelerating the decline in stock prices. Acadian eliminated both positions from its portion of the Fund in the third quarter of 2021.

At the end of the Fund's fiscal period, Acadian had its largest overweight country positions in Taiwan, Denmark, and Australia. Japan, the UK, and Canada were the largest underweight positions. At the sector level, the emphasis was on healthcare, energy, and materials, while consumer discretionary and financials were considerably underweighted.

Baillie Gifford

Baillie Gifford maintains its investment philosophy and process through changing market environments. Baillie Gifford fundamentally believes in long-term investing, and that share prices ultimately follow earnings growth. Baillie Gifford is focused on finding companies whose ability to generate earnings growth is independent of a particular market environment.

The financials and healthcare sectors were the largest detractors from performance in Baillie Gifford’s portion of the Fund during the 12-month period. Stock selection was the root cause of the underperformance. There was also a slight drag on performance from asset allocation within both sectors. Baillie Gifford had underweight positions in both financials and healthcare, which proved detrimental as those sectors rose.

Information technology (IT) made a marginal contribution to Baillie Gifford’s portion of the Fund. A small stock selector contribution was offset by a small asset allocation drag. IT was the only sector to contribute positively to performance during the Fund’s fiscal period.

Baillie Gifford’s portion of the Fund was also hindered during the fiscal year as several Chinese companies that had benefited from a return of consumer demand early in the period once again underperformed as the new COVID-19 variants took hold. The conflict in Ukraine also hurt performance, as two small Russian investments were revalued to zero.

IMCD NV and Kingspan Group PLC both contributed positively to Baillie Gifford’s portion of the Fund during the fiscal year. IMCD, a Dutch specialty chemicals distributor, continued its merger and acquisition strategy into 2021 and 2022 with the addition of more than 200 million euros in sales across 11 acquisitions. IMCD has increased group profit 10% over the last five years through acquisitions versus 5% organically.

Kingspan Group, the family-owned Irish manufacturer of commercial and residential insulation materials, performed strongly for Baillie Gifford’s portion of the Fund after providing support for the green

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Portfolio management review
Optimum International Fund

infrastructure sector. The company upgraded its outlook for 2022 but still cautions that supply-chain issues remain.

Ping An Healthcare & Technology Co. Ltd. and Tencent Music Entertainment Group both detracted from performance in Baillie Gifford’s portion of the Fund. Ping An was among the Chinese technology companies affected by investors concerned with new regulations. However, the company’s operational story remained strong, in Baillie Gifford’s opinion. Ping An utilizes artificial-intelligence (AI)-based software to make diagnoses. Medical consultations continued to grow, as does the software’s ability to recognize illness. Right now, although AI is “assisting” in diagnosis, regulators have yet to approve its use as a replacement for a doctor’s diagnosis.

Tencent Music Entertainment, the Chinese music-streaming business, continued to grow significantly across multiple platforms.

The company reported a record 4.9 million net new users as part of its first-quarter earnings release. The announcement of further organic investment, particularly in long-form audio (LFA), weighed on shares in the latter part of the Fund’s fiscal year but is an investment Baillie Gifford believes will ultimately help build out the network. The entire Tencent network integrates Tencent Cloud Real-time Communication Network, Instant Messaging Network, and Streaming Media Distribution Network. Combined, the services provide infrastructure for music and live streaming.

Overall, Optimum International Fund used derivatives, including foreign currency exchange contracts, during the fiscal year. However, these had a minimal effect on performance.

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Portfolio management review
Optimum Large Cap Growth Fund

March 31, 2022 (Unaudited)

Past performance does not guarantee future results.

For complete, annualized performance for Optimum Large Cap Growth Fund, please see the table on page 25.

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

The performance of Class A shares excludes the applicable sales charge. Both Institutional Class shares and Class A shares reflect the reinvestment of all distributions.

Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index.

Fund objective

The Fund seeks long-term growth of capital.

Advisor

Delaware Management Company (DMC)

Sub-advisors

ClearBridge Investments, LLC (ClearBridge)
T. Rowe Price Associates, Inc. (T. Rowe Price)

Market review

Equities markets in the US climbed steadily through the first nine months of the fiscal year ended March 31, 2022, buoyed by robust corporate earnings, ample liquidity, and progress in bringing the global pandemic under control. Widespread vaccination spurred a reopening of most parts of the global economy and contributed to a healthy labor market that restored most of the jobs that had been lost due to pandemic lockdowns and related restrictions on economic activity.

Even as equities were rising, inflation and strained supply chains began to dampen investors’ enthusiasm. Although the US Federal Reserve initially declared that inflation was transitory, prices continued to rise, and in February 2022, the US Consumer Price Index showed the largest year-over-year increase in 40 years, adding to market volatility that had begun in January.

Stocks slumped further when Russia invaded Ukraine in late February, prompting the US and many other nations, especially in Europe, to respond with broad and damaging economic sanctions targeting key Russian individuals and institutions.

In March 2022, attempting to take control of inflation, the Fed raised rates 0.25%, its first increase since 2018. At the time, the Fed indicated that additional rates were forthcoming, that the size of the increases could grow to 0.5%, and that it would begin drawing down its balance sheet.

In the final weeks of the 12-month period, equities did recover somewhat and, despite the pressures of inflation, the war in Ukraine, supply chain disruptions, and the ongoing pandemic, the large cap S&P 500^® Index advanced 15.65% for the 12-month period. Large-cap growth stocks maintained an edge over their value counterpart, with the benchmark Russell 1000 Growth Index rising 14.98% for the year while the Russell 1000^® Value Index added 11.67%.

Source: Bloomberg, unless noted otherwise.

Fund performance

Optimum Large Cap Growth Fund underperformed its benchmark, the Russell 1000 Growth Index, for the Fund’s fiscal year ended March 31, 2022. Both ClearBridge’s and T. Rowe Price’s portions of the Fund underperformed the benchmark, citing adverse stock selection and, in the case of ClearBridge, adverse sector allocation decisions as well. In ClearBridge’s portion of the Fund, stock selection in the communication services, information technology (IT) and consumer discretionary sectors, an underweight to the IT sector, and an overweight to the consumer discretionary sector detracted from relative performance. In T. Rowe Price’s portion of the Fund, the IT, communication services, and consumer discretionary sectors were the major detractors, while the healthcare and materials sectors contributed to relative returns.

ClearBridge

ClearBridge normally invests in equity securities (or other instruments with similar economic characteristics) of US companies with large market capitalizations. ClearBridge’s core holdings are large-capitalization companies that it believes to be dominant in their industries due to product, distribution, or service strength.

After making aggressive positioning moves to increase the up capture of the Fund during the 12-month period, ClearBridge’s actions over the last year focused on adding exposure to secular trends such as: ecommerce and payments through the additions of Nike Inc. and PayPal Holdings Inc.; gaming through the purchase of Unity Software Inc.; electrification of the economy via Eaton Corp. PLC; and a shift in healthcare to innovative and market leading

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Optimum Large Cap Growth Fund

medical device makers, such as Intuitive Surgical Inc. and DexCom Inc., that ClearBridge thinks should benefit from a renewed focus on elective procedures and treatment of chronic conditions.

Communication services was the primary detractor from performance in ClearBridge’s portion of the Fund. In the second half of the fiscal period, ClearBridge’s overweight to social media and digital advertising platform Meta Platforms Inc. (Facebook) negatively affected results. Shares declined following fourth-quarter earnings results and first-quarter revenue guidance that were weaker than expected.

Weakness in the digital payments space held back several IT holdings in ClearBridge’s portion of the Fund, including Fidelity National Information Services Inc. and PayPal Holdings Inc.,as the pandemic eased its grip on the economy and consumers returned to brick-and-mortar establishments.

ClearBridge initiated a position in PayPal after the shares had already fallen 40% from their all-time high but PayPal's muted outlook was not fully priced in at that point. Nevertheless, ClearBridge believes PayPal is fundamentally holding share in the digital payments industry and is set up for continued growth in ecommerce once reopening headwinds pass. The company onboarded nearly 120 million net new users over the last few years; naturally, many users will churn off the platform. ClearBridge also sees the company’s strategy to add additional use cases to its wallet such as investing, crypto, savings accounts, and bill pay as catalysts to accelerate revenue growth over time. In addition, ClearBridge believes Venmo continues to be under-monetized, and a new partnership with Amazon.com will be something to watch. Therefore, ClearBridge continues to hold PayPal in its portion of the Fund.

Fidelity National Information Services has topped earnings forecasts the last two quarters, but investors are focused on the merchant business which has been decelerating year over year. Concerns remain that the company is not competitive with new/modern acquirers in its merchant segment; however, the company expects to deliver double-digit revenue growth in this area given its expanding capabilities and ongoing merchant wins and remains undervalued versus peers. 2022 results remain heavily dependent on the speed of the travel/spending recovery. While current quarter guidance came in below expectations, the company’s full-year earnings and revenue forecasts are in-line to slightly higher than Wall Street, providing optimism over continued improvement. ClearBridge believes Fidelity National Information Services remains a good way to participate in the growth of digital payments and discretionary travel spending and therefore continues to hold it in its portion of the Fund.

Two other IT holdings contributed but could not fully offset the sector’s losses. Palo Alto Networks Inc., a provider of enterprise security solutions, got a boost from the threats posed by the Russian-Ukraine conflict. Microsoft Corp., developer of the Windows and Office family of products among others, has proven to be defensive through periods of market turbulence and this fiscal year was no exception.

Alibaba Group Holding Ltd., in the consumer discretionary sector, is a Chinese ecommerce and digital payments provider that detracted from ClearBridge’s portion of the Fund. Its shares declined as the company faced increased regulatory scrutiny from the Chinese government and a return of COVID-19 adversely affected ecommerce activity. ClearBridge continues to view Alibaba as a durable business with the potential for sustained revenue and profit growth due to its size, balance sheet, and importance to the Chinese economy.

Additional communications sector detractors from performance in ClearBridge's portion of the Fund were Netflix Inc., Sea Ltd., and Walt Disney Co. Netflix is a leading provider of streaming media programming. After being a prime beneficiary of increased viewing patterns during the stay-at-home period of COVID-19, Netflix is recalibrating how to measure and forecast subscriber growth as global economies fully reopen. The company's stock fell sharply after Netflix modestly reduced its net subscriber additions for the first quarter of 2022, causing us to question its ability to continue to deliver double-digit subscriber growth. While Netflix has suffered further subscriber declines and price pressures in international markets, ClearBridge believes it is taking aggressive actions to address these issues, and ClearBridge remains convinced that its thesis for owning the stock is intact. Sea is a Singapore-based platform for ecommerce, digital payments, and gaming. Sea underperformed owing to a general sell-off in higher multiple stocks and weakening of its gaming segment. In gaming, the company has seen a slowdown in bookings growth in the wake of economic reopening – a trend seen at other gaming platforms like Roblox. ClearBridge remains optimistic about Sea due to what it views as its compelling growth opportunity in ecommerce and digital payments, businesses where it has a strong execution track record. Walt Disney is an entertainment company that conducts operations in media networks, studio entertainment, theme parks and resorts, consumer products, and interactive media. Disney detracted from the performance of ClearBridge's portion of the Fund owing to weakness in Disney+ subscriber momentum. ClearBridge believes Disney's slowdown is largely tied to production delays as the company aims to significantly expand content availability and subscriber momentum has begun to show signs of improvement.

The healthcare sector was the primary contributor to performance in ClearBridge’s portion of the Fund, led by strong operating results from UnitedHealth Group Inc. UnitedHealth continues to offer consistent growth from a diversified, scaled base of healthcare insurance and service businesses. ClearBridge also realized strong

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results from Thermo Fisher Scientific Inc., a diversified provider of life sciences solutions, analytical instruments, specialty diagnostics, and laboratory products and services. Animal health provider Zoetis Inc. was another notable contributor.

T. Rowe Price

T. Rowe Price normally invests in stocks of large-capitalization companies with one or more of the following characteristics: strong cash flow and an above-average rate of earnings growth; the ability to sustain earnings momentum during economic downturns; and occupation of a lucrative niche in the economy and ability to expand even during times of slow economic growth. As the US and the world work to return to normal, T. Rowe Price is monitoring several key market themes.

IT was the leading relative underperformer in T. Rowe Price’s portion of the Fund, due primarily to weak stock choices led by underweight positions in Apple Inc. and NVIDIA Corp. Shares of Apple gained over the 12-month period, driven by the strength of the iPad and Mac, which benefited from coronavirus-pandemic tailwinds. Shares of NVIDIA also climbed higher during the fiscal year as the company’s data center business showed signs of reacceleration, underpinned by the demand for chips that can support artificial intelligence (AI) and deep learning applications.

Communication services also hampered relative performance in T. Rowe Price’s portion of the Fund, due to unfavorable stock picks coupled with an overweight allocation. Within the sector, holdings in Sea Ltd. and Snap Inc. detracted from relative performance. Shares of Sea traded lower in response to disappointing guidance for its gaming business. T. Rowe Price believes Sea’s platform is well positioned to gain share in Southeast Asia’s high-margin online gaming market and expand its reach to additional emerging market countries. Shares of Snap, the company behind Snapchat and other camera-based applications, sold off when results were affected by the one-two punch of Apple’s new consumer-tracking restrictions and by the combination of supply chain disruptions and labor shortages. Snap's control of the impressionable and highly engaged youth demographic, relatively low ad load, and culture of innovation combine to form what T. Rowe Price views as a tightly coiled monetization spring. T. Rowe Price believes that network effects and innovations in technology will continue to drive user growth and engagement, paving the way for potential earnings growth over time and continues to hold Sea and Snap in its portion of the Fund.

Consumer discretionary also hampered relative performance in T. Rowe Price’s portion of the Fund due to weak stock picks such as Rivian Automotive Inc. Shares of Rivian came under pressure as the early-stage electric-vehicle maker was penalized for various items, including a small production target miss in 2021, the departure of its COO, an inflation-driven price increase, and lowered 2022 delivery guidance due to supply chain issues. T. Rowe Price strongly believes that Rivian’s recent underperformance equates to short-term noise for a young company that is implementing new technologies in a notoriously difficult industry during a material global supply chain disruption amid record levels of inflation and thinks Rivian is well positioned to benefit from the automotive industry’s electrification. T. Rowe Price continues to hold Rivian in its portion of the Fund.

In contrast, the healthcare sector contributed to T. Rowe Price’s portion of the Fund, due to stock selection coupled with an underweight exposure. Shares of UnitedHealth Group Inc. traded higher as the company guided earnings growth higher for 2022. Shares of HCA Healthcare Inc. benefited from the increase in demand for hospital services, leading to higher patient volumes and outpatient surgeries. The company also unveiled plans to build a new free-standing emergency facility in Central Florida. Additionally, investors appeared to react positively to news of a stock buyback and a dividend increase.

A significant underweight exposure to the materials sector also positively affected relative returns in T. Rowe Price’s portion of the Fund.

Overall, Optimum Large Cap Growth Fund used derivatives, including foreign currency exchange contracts, during the fiscal year. However, these had a minimal effect on performance.

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Portfolio management review
Optimum Large Cap Value Fund

March 31, 2022 (Unaudited)

Past performance does not guarantee future results.

For complete, annualized performance for Optimum Large Cap Value Fund, please see the table on page 28.

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

The performance of Class A shares excludes the applicable sales charge. Both Institutional Class shares and Class A shares reflect the reinvestment of all distributions.

Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index.

Investment objective

The Fund seeks long-term growth of capital and may also seek income.

Advisor

Delaware Management Company (DMC)

Sub-advisors

Massachusetts Financial Services Company (MFS)

Rothschild & Co

Market review

US equities performed well in the first nine months of the fiscal year ended March 31, 2022, before entering a spate of volatility that marred the opening months of the new year. Equities regained much of their footing in March, however, delivering a gain of 15.65% for the 12-month period, as measured by the S&P 500^® Index.

There were challenges throughout the period. Multiple waves of COVID-19, including the highly transmissible Delta and Omicron variants, briefly interrupted the markets’ rise, as did the onset of inflation, which the US Federal Reserve initially labeled as transitory. Supply chain disruptions, notably in important commodity markets, and a tight labor market also caused brief investor stumbles. But low unemployment and continued healthy corporate profits were more than sufficient to keep equity markets advancing through the end of 2021.

As 2022 began, however, just as the Omicron wave of the pandemic appeared to recede in much of the world, markets experienced a geopolitical shock as Russia first built up troops on Ukraine’s border and then launched a full-scale invasion. Given Europe's heavy reliance on imported oil and gas from Russia, European markets were among the hardest hit. Energy prices spiked in the wake of the invasion, adding to an already multidecade high level of inflation. Non-energy commodities rose sharply as well. Both the equity and fixed income markets experienced significant upticks in volatility.

The ripple effects from the Russian invasion further complicated central banks’ efforts to rein in inflation. Energy shocks have historically resulted in global growth slowdowns, if not pullbacks, so policymakers find themselves in the difficult position of trying to restrain inflation without tipping economies into recession. Accordingly, expectations for central banks to aggressively tighten monetary policy have moderated.

Against an environment of rising labor and raw materials prices, higher interest rates, and waning fiscal and monetary stimulus, investors have become increasingly anxious that corporate profit margins may be past peak for this cycle. That said, tentative signs of some supply chain bottlenecks easing, low levels of unemployment across developed markets, and the loosening of coronavirus restrictions seem to be supportive for the macroeconomic backdrop.

Source: Bloomberg, unless noted otherwise.

Fund performance

Optimum Large Cap Value Fund outperformed its benchmark, the Russell 1000 Value Index, for the fiscal year ended March 31, 2022. While the Rothschild & Co portion of the Fund outperformed the benchmark return, the MFS portion of the Fund slightly underperformed.

In Rothschild & Co’s portion of the Fund, outperformance was supported largely by favorable stock selection. Sector allocation also contributed positively to relative returns. While a modest cash position acted as a headwind to relative performance during a period of healthy absolute returns, Rothschild & Co’s overweight position in energy contributed to performance owing to a sharp rise in oil prices against the backdrop of supply constraints. Rothschild & Co’s stock selection was especially positive in the technology, manufacturing, and healthcare sectors, more than offsetting weakness in the basic materials, consumer services, and transportation sectors. An underweight position in energy and adverse stock selection in the materials sector hindered performance in the MFS portion of the Fund. Advantageous stock selection in the industrials sector partially offset this, however. An underweight position and stock selection in

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the consumer discretionary sector contributed to performance in the MFS portion of the Fund.

MFS

MFS has maintained a consistent investment approach since this strategy’s inception. For its portion of the Fund, MFS uses a long-term time horizon in making investment decisions. MFS maintains a disciplined investment philosophy and process that is always focused on investing in high-quality companies trading at inexpensive valuations. As was the case last year, MFS continued to assess the impact of significant changes to the global economic outlook and equity markets. Over the past year, these included rising inflation, interest rates, uncertain monetary policy, slowing growth, the war in Ukraine, and the ongoing pandemic.

As energy prices climbed throughout the period, the sector performed well and detracted from performance in the MFS portion of the Fund, which was underweight the sector. Not owning integrated oil and gas company Exxon Mobil Corp. detracted from performance, as did the combination of first underweighting and later exiting a position in integrated energy company Chevron Corp. As a result, MFS missed the shares’ significant rally toward the end of the Fund’s fiscal year.

Security selection in the materials sector hampered relative results in the MFS portion of the Fund, led by an overweight position in coatings company PPG Industries Inc.

In other sectors, MFS did not own insurance and investment firm Berkshire Hathaway Inc. and health insurance and Medicare-Medicaid provider UnitedHealth Group Inc. Both decisions detracted from performance. MFS maintained overweight positions in shares of diversified financial services firm Citigroup Inc., global financial services firm JPMorgan Chase & Co., media and technology company Comcast Corp., power and hand tools provider Stanley Black & Decker Inc., and diversified technology and manufacturing company Honeywell International Inc., all of which weighed on relative returns.

In the industrials sector, MFS maintained an overweight holding of global security company Northrop Grumman Corp. that contributed positively to relative performance. Northrop Grumman Corp. is engaged in the provision of security services including cybersecurity for computers and communications. MFS avoided a position in aerospace firm The Boeing Co., which performed poorly, thereby also contributing to relative returns.

Stocks in other sectors that contributed positively to relative performance in the MFS portion of the Fund included overweight positions in shares of risk-management and human-capital consulting services provider Aon PLC, risk and insurance consulting firm Marsh & McLennan Cos. Inc., property and casualty insurance provider Chubb Ltd., health services and information technology company McKesson Corp., oil and gas company ConocoPhillips, and IT servicing firm Accenture PLC. Avoiding poor-performing diversified entertainment firm The Walt Disney Co. and telecommunication services provider AT&T Inc. also added to positive results.

Rothschild & Co

Rothschild & Co employs an integrated approach that balances quantitative analysis, fundamental research, and risk management guidelines to identify stocks of companies it believes possess attractive relative valuation and an ability to exceed market expectations. Rothschild & Co’s investment process has been stable through many market cycles, maintaining a consistent approach even as economic and market environments fluctuate. That said, the market environment experienced during the most recent fiscal period was unprecedented, reflecting the pandemic and the resulting government fiscal support and central bank monetary support. Unprecedented monetary support accompanied by two shocks in two years to global supply chains has significantly raised inflationary expectations above the Fed’s comfort level. We believe that such environments characterized by volatility can unearth opportunities as pricing inefficiencies develop at the stock level, which is where we focus our attention.

Although the technology sector underperformed within the benchmark, the Rothschild & Co portion of the Fund benefited from advantageous stock selection in the sector, both in terms of what it owned, including Alphabet Inc., Broadcom Inc., and Microsoft Corp., and what it avoided, including an underweight position in Intel Corp. and no exposure to Salesforce Inc.

Manufacturing was also a strong contributor to performance in the Rothschild & Co portion of the Fund, as defense companies Lockheed Martin Corp. and Northrop Grumman Corp. both benefited from the war in Ukraine.

Individual stocks that contributed to performance in the Rothschild & Co portion of the Fund included ConocoPhillips, an energy exploration and production company. The rise in crude oil prices that resulted, in part, from the Russian invasion of Ukraine drove share prices here. Schlumberger NV, the largest US oilfield services company with a focus on international markets, also contributed to performance significantly.

Rothschild & Co’s portion of the Fund underperformed in the basic materials sector largely because of its lack of investment in commodity-specific industries, such as copper and steel, which rallied on the supply constraints caused by the Russia-Ukraine crisis. Rothschild & Co’s direct commodity exposure lies exclusively in the oil sector, which aided performance.

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Portfolio management review
Optimum Large Cap Value Fund

Although the utilities sector outperformed the overall benchmark by a wide margin, one of Rothschild & Co’s holdings in the sector, NextEra Energy Inc., did not keep pace with the peer group and detracted from performance.

Individual stocks that detracted from the Rothschild & Co portion of the Fund included Global Payments Inc., which provides electronic transaction processing, information systems, and services. The stock underperformed despite reporting above-consensus revenue and earnings and providing optimistic longer-term financial targets.

Southwest Airlines Co. also detracted from performance in the Rothschild & Co portion of the Fund. Southwest is a budget-friendly airline operator with its exposure predominantly in the US. The stock has lagged as the recovery has been choppy. Rothschild & Co continues to hold the shares given that Southwest has one of the strongest balance sheets among peers and the least exposure to business travel, which is recovering slowly and could be structurally impaired.

Overall, Optimum Large Cap Value Fund used derivatives, including foreign currency exchange contracts, during the fiscal year. However, these had a minimal effect on performance.

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Portfolio management review
Optimum Small-Mid Cap Growth Fund

March 31, 2022 (Unaudited)

Past performance does not guarantee future results.

For complete, annualized performance for Optimum Small-Mid Cap Growth Fund, please see the table on page 31.
Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.
The performance of Class A shares excludes the applicable sales charge. Both Institutional Class shares and Class A shares reflect the reinvestment of all distributions.
Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index.

Investment objective

The Fund seeks long-term growth of capital.

Advisor

Delaware Management Company (DMC)

Sub-advisors

Columbus Circle Investors (CCI)
Peregrine Capital Management, LLC (PCM)

Market review

Rising COVID-19 infections, a rapid increase in inflation, continued supply chain bottlenecks, and the onset of the conflict in Ukraine led to increased market volatility during the fiscal year. With a meaningful portion of the US population fully vaccinated, the reopening of the broader economy progressed quickly early in the Fund’s fiscal year. This drove significant pent-up demand for goods and services and put immense pressure on global supply chains, logistics networks, and labor forces to keep up.

A global spike in the Delta and Omicron variants of COVID-19, coupled with the continuing conflict in Ukraine, then put further stress on worldwide supply chains. This helped push inflation to historically high levels and forced the US Federal Reserve to pivot to a more hawkish stance despite early signs of a slowing economy.

Stocks faced broad selling pressure in March 2022, as growth equities led the market lower and smaller-cap stocks lagged their larger-cap peers. A confluence of tighter monetary policy with an intensification of unsettling geopolitical events in Europe sparked global stagflation fears, causing many investors to dump shares of more speculative stocks.

Source: Bloomberg, unless noted otherwise.

Fund performance

Optimum Small-Mid Cap Growth Fund declined, although it outperformed its benchmark, the Russell 2500 Growth Index, for the fiscal year. Both CCI’s and PCM’s portions of the Fund outperformed the benchmark. Although both growth and value stocks lost ground during the Fund’s fiscal period, CCI’s portion of the Fund benefited on a relative basis from its comparatively balanced positioning in both cyclical and secularly driven growth stories and the market’s focus on rewarding stronger fundamentals. PCM’s high growth yet valuation sensitive approach generated strong relative outperformance during the fiscal year, despite the economic uncertainty. Outperformance in PCM’s portion of the Fund relative to the benchmark was due to stock selection in the healthcare and industrial sectors.

CCI

CCI uses a growth-oriented investment philosophy of “positive momentum and positive surprise” to strive to invest in what CCI views as strong companies getting stronger and in companies whose fundamentals are exceeding investor expectations.

Due to favorable stock selection, the healthcare and financials sectors were the leading contributors in CCI’s portion of the Fund. Conversely, unfavorable stock selection in the information technology (IT) sector and an underweight in the real estate sector detracted from CCI’s portion of the Fund.

Arista Networks Inc. a provider of cloud networking solutions, was CCI’s largest contributor to performance in its portion of the Fund for the fiscal year. The company benefited from a multi-year upgrade cycle within its hyperscale segment as customers such as Facebook and Microsoft upgraded their networks. Share gains within Arista Network’s enterprise segment also contributed.

Matador Resources Co., an energy company focused on the development of oil reserves in the Delaware and Eagle Ford shale areas of Texas, was the second largest contributor to performance within CCI’s portion of the Fund. Continued improvements in horizontal drilling and well-completion techniques, along with significantly higher oil prices, combined to propel oil and gas economics higher. In addition, the favorable commodity price backdrop improved Matador’s free cash flow outlook, creating an opportunity for potential dividend and stock buyback announcements.

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Portfolio management review
Optimum Small-Mid Cap Growth Fund

Natera Inc., a genetic testing company focused on prenatal testing (NIPT), organ transplant rejection, and cancer recurrence monitoring, detracted the most from performance in CCI’s portion of the Fund. Its shares declined despite continued robust fundamentals that supported CCI’s investment thesis. CCI attributes the decline in shares to profit-taking in highly valued growth stocks when the market rotated toward cyclical and value shares during 2021. Notably, the stock came under further pressure after CCI exited its position in Natera.

Levi Strauss & Co., a leading apparel company focused on denim, also detracted from performance in CCI’s portion of the Fund. Despite strong quarterly results, supported by a cyclical recovery and a new jeans fashion cycle, shares declined as the market struggled with increasing cost inflation, supply chain headwinds, and the potential impact of higher inflation on consumer spending, leading CCI to exit the holding.

CCI believes slower economic growth ahead with a more restrictive Fed should favor the discipline it follows in its portion of the Fund as the market increasingly gravitates toward companies that can demonstrate continued positive momentum and positive earnings surprises. Recent leading economic indicators, including weaker purchasing managers’ indices (PMIs), waning consumer confidence, and a brief yield curve inversion, all seem supportive of this view. Given CCI’s belief that the risks associated with cyclical companies are likely to increase, CCI began to add more durable-secularly driven, positively surprising, growth stocks typical of its investment discipline to its portion of the Fund. CCI thinks these companies have the potential to stand out and may disproportionately benefit as growth becomes increasingly scarce.

CCI’s portion of the Fund is most overweight the healthcare sector. CCI recently increased its weighting in what it views as medical technology companies with innovative products that can benefit from robust secular demand and the resumption of medical procedures as COVID-19 recedes. CCI’s portion of the Fund is also overweight the communication services sector, particularly those companies experiencing strong demand from digital business models in software, advertising, and entertainment.

CCI’s portion of the Fund is most underweight the consumer discretionary sector, as fading stimulus payments along with persistently high inflation are likely to squeeze consumer pocketbooks, prompting a pullback in consumer spending. CCI also continues to have no exposure to the real estate sector, as real estate investment trusts (REITs) are at risk from rising interest rates.

CCI's portion of the Fund did not hold derivatives during the fiscal year.

PCM

The healthcare and industrials sectors were the strongest contributors to performance for PCM’s portion of the Fund for the fiscal year. Contribution from the healthcare sector was broad based, with favorable stock selection across life sciences, healthcare technology, biotechnology, and healthcare provider holdings. An underweight position to the biotechnology industry group also contributed to performance for PCM’s portion of the Fund. Within the industrials sector, improved economic visibility and attractive valuations drove a resurgence in many of the market’s more cyclical areas. PCM’s electronic equipment and professional services holdings were notable contributors for the Fund’s fiscal period.

The energy and real estate sectors detracted the most from performance within PMC’s portion of the Fund. Driven by the continued economic recovery as well as the Russia-Ukraine war, global energy prices rose rapidly, driving strong stock performance across the energy sector. PCM’s portion of the Fund was underweight energy during the 12-month period, which detracted from relative results. PCM’s underweight position to the outperforming real estate sector also was a modest detractor.

The principal contributor to PCM’s portion of the Fund for the fiscal year was Mimecast Ltd. Mimecast is a leading provider of cloud-based email security solutions focused on small- and medium-sized businesses. Email security is a top priority for any organization, especially with the work-from-home trend significantly increasing a company’s exposure to email-based threats. As a result, demand for Mimecast’s security products accelerated throughout the Fund’s fiscal period, with increasing order sizes and the strong up-sell of new products to both new and existing customers. Given Mimecast’s strong growth prospects and rapid consolidation within the cybersecurity space, private equity firm Permira acquired the company in December.

Another significant contributor was Steel Dynamics Inc., one of the largest US steel producers and metal recyclers. Coupled with a strong pricing environment, the company has benefited from an improved economic backdrop as demand for steel remained robust. Not only has Steel Dynamics seen particular strength in the nonresidential construction market, PCM thinks that the eventual recovery in automotive production volumes should be additive to its future growth as well. As a result of these strong end-market dynamics, free cash flow was robust, enabling the company to repurchase roughly 8% of its total outstanding shares in calendar year 2021.

The leading detractor from performance in PCM’s portion of the Fund was Sleep Number Corp., a designer and manufacturer of premium mattresses. Since consumers spent more time in their homes during the pandemic, demand for home goods, including mattresses, had

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been strong. And while the demand environment for the company’s products remains favorable, supply chain delays hurt sales and earnings results for much of the fiscal year. A shortage of semiconductors used in the adjustable base of the beds caused persistent delays in customer deliveries during the fiscal year, leading the stock to underperform. PCM continues to hold Sleep Number in its portion of the Fund.

Tactile Systems Technology Inc. also detracted from performance in PCM’s portion of the Fund. Tactile Systems designs and manufactures medical devices used for the treatment of lymphedema, an underdiagnosed and undertreated affliction affecting 1.4 million new patients annually. COVID-19-related headwinds were the primary driver of the stock’s weakness for the Fund’s fiscal period. With multiple variants emerging over the period, patients were unpredictable in their willingness to return to their doctors’ offices. Meanwhile, vaccine mandates at both the federal and company level hurt Tactile Systems’ ability to attract and retain its salesforce. While this led to volatile sales and earnings results during the 12-month period, PCM believes the company’s valuation remains attractive for its long-term growth potential, especially as the economy continues to reopen. PCM continues to hold Tactile Systems in its portion of the Fund.

PCM’s process focuses on rapidly growing small-cap companies trading at valuations that in PCM’s opinion do not yet reflect that strong growth. PCM’s portion of the Fund is currently most overweight companies in the industrial and financial sectors, and most underweight in consumer discretionary.

PCM's portion of the Fund did not hold derivatives during the fiscal year.

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Portfolio management review
Optimum Small-Mid Cap Value Fund

March 31, 2022 (Unaudited)

Past performance does not guarantee future results.

For complete, annualized performance for Optimum Small-Mid Cap Value Fund, please see the table on page 34.
Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.
The performance of Class A shares excludes the applicable sales charge. Both Institutional Class shares and Class A shares reflect the reinvestment of all distributions.
Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index.

Fund objective

The Fund seeks long-term growth of capital.

Advisor

Delaware Management Company (DMC)

Sub-advisors

LSV Asset Management (LSV)
Cardinal Capital Management LLC (Cardinal)

Market review

Small- and mid-cap value equities in the US performed well in the beginning of the Fund’s fiscal year ended March 31, 2022, as the COVID-19 vaccination rollout continued to accelerate globally, supporting a rebound in economic activity. Later in the period, global supply chain disruptions hurt company results and rising inflation eroded investor optimism. Markets, however, proved to be reasonably resilient despite these challenges and the emergence of the Delta and Omicron COVID-19 variants. Strong earnings continued to support elevated equity valuations as market indices finished the calendar year of 2021 with notably strong performances.

In the first quarter of 2022, however, Russia’s invasion of Ukraine and the resulting humanitarian crisis jolted markets as numerous sanctions caused a commodity supply shock and increased inflationary pressures. Within the US, value stocks broadly held up well relative to growth stocks during the period. Representing US small- to mid-cap stocks, the Russell 2500 Value Index was up 7.7% while the Russell 2500^TM Growth Index dropped 10.1% for the fiscal year.

Overall, large-cap stocks significantly outpaced small- and small-to-mid-cap stocks, as the S&P 500^® Index rose more 15.6% for the fiscal year. Small- to mid-cap stock performance was inconsistent as economically sensitive sectors, such as energy and materials, significantly outperformed while consumer discretionary, information technology, and industrials stocks lagged. Outside of this, defensive investments such as utilities, consumer staples, and real estate all fared better, reflecting investors' increased appetite for a degree of certainty and security.

Source: Bloomberg, unless noted otherwise.

Fund performance

Optimum Small-Mid Cap Value Fund underperformed its benchmark, the Russell 2500 Value Index, for the fiscal year. LSV’s portion of the Fund outperformed the benchmark for the fiscal year, benefiting from its deeper value positioning relative to the benchmark. Cardinal’s portion of the Fund trailed the benchmark for the fiscal year because of its lack of exposure to commodity-sensitive and more cyclical stocks.

LSV

The positive impact of LSV’s portion of the Fund relative to the benchmark was evident in stock selection, where that portion of the Fund’s deeper value positioning relative to the benchmark contributed to performance. Stock selection was particularly strong in the financials, healthcare, and technology sectors. Sector selection detracted mostly because of an underweight to energy stocks. This had a significant effect on relative performance, as energy stocks outperformed the broader market by a wide margin. An overweight to consumer discretionary stocks also detracted from performance.

LSV’s portion of the Fund was broadly diversified with 223 stocks, during the fiscal year, which limited the potential impact of any one position on relative performance. The two leading contributors to relative performance were The Mosaic Co., the largest US producer of potash and phosphate fertilizer, and Atkore Inc., a leading provider of electrical, safety, and infrastructure solutions. Both companies benefited from the continued favorable environment for high-quality companies that are generating cash and paying dividends. LSV believes both stocks remain attractively valued, and it continues to hold them in its portion of the Fund.

The two leading performance detractors from LSV’s portion of the Fund were Whirlpool Corp. and Sleep Number Corp. Whirlpool, which markets and distributes major home appliances and related

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products, was the largest detractor within LSV’s portion of the Fund. There does not appear to be any discernible reason for the stock’s decline during the quarter other than headwinds created by a potential economic slowdown. 2021 was a good year for Whirlpool, as consumer demand was strong and gross profits and operating margins increased. LSV believes its low valuation is not justified. Whirlpool continues to rank highly in the LSV model and continues to be held in LSV’s portion of the Fund.

Sleep Number, a manufacturer of beds and bedding accessories, had earnings revised downward after supply chain pressures hurt its business. Sleep Number remains attractively valued by LSV’s model and is still held in LSV’s portion of the Fund.

As a contrarian deep value investor, LSV has patiently stuck to its discipline. LSV maintains a strong conviction that valuations matter and believes that conditions continue to be favorable for value stocks and in particular the deep value stocks it owns. Importantly, LSV believes that the deeply discounted stocks owned in LSV’s portion of the Fund are a high-quality blend of profitable companies that are generating cash, paying dividends, and buying back stock. LSV believes that overall quality profile is higher than the Russell 2500 Value Index and comparable to the core Russell 2500 Index. While the short-term environment resulting from the pandemic and Russia’s invasion of Ukraine remain uncertain, LSV believes the mid- to long-term prospects for holdings in its portion of the Fund are attractive. Regardless of current market sentiment, LSV remains committed to its disciplined deep value approach.

LSV’s portion of the Fund did not hold derivatives during the fiscal year.

Cardinal

While Cardinal's portion of the Fund kept pace with its benchmark, the Russell 2500 Value Index, for much of the fiscal year and added considerable value in late 2021 and early 2022, Russia's invasion of Ukraine and associated commodity-driven rally caused the portfolio to lag sharply in March, which offset the earlier outperformance. For the fiscal year, Cardinal's portion of the Fund slightly lagged the benchmark. Cardinal's focus on owning high-quality businesses and low exposure to commodity-sensitive and highly cyclical stocks drove the relative underperformance of Cardinal’s portion of the Fund.

In managing its portion of the Fund's assets, Cardinal employs a cash-flow-oriented investment process. Cardinal believes that a company's stock price is ultimately determined by its ability to generate excess cash flow and redeploy that cash to enhance shareholder value. The investment process involves making detailed five-year projections based on an analysis of the company's business and financials as well as discussions with the company's management and knowledgeable third parties. Cardinal looks for companies with significant free cash flow, stable and predictable business models, and a motivated and competent management team.

The leading detractors within Cardinal’s portion of the Fund were in the financials and materials sectors, while major contributors came in the healthcare and consumer discretionary sectors. In financials, stock selection and not owning insurance stocks were the main drivers of the underperformance. Cardinal tends not to own insurance companies because of what it believes is insufficient transparency into their operations and reserves. Specifically, shares of Columbia Banking System Inc. lagged other regional banks after it announced the acquisition of neighboring Umpqua Holdings at a premium valuation in October. Cardinal continues to hold shares of Columbia in its portion of the Fund as it is a beneficiary of a higher interest rate environment given its low-cost deposit base. Also, Columbia Bank anticipates substantial synergies from the merger with Umpqua, which should close by mid-year 2022, and Columbia’s shares now sell at a discount to other regional banks.

Stock selection and not owning metals and mining stocks were the leading detractors from performance in the materials sector for Cardinal’s portion of the Fund. Cardinal does not view most metals and mining stocks as sufficiently stable or predictable to consistently generate free cash flow or to possess attractive reinvestment opportunities. In addition, the stock price of Axalta Coating Systems Ltd. declined amid broad weakness in specialty chemicals stocks – a response to chip shortages and supply chain constraints that affected its automobile manufacturing customers and higher-than-expected raw material inflation. Cardinal’s portion of the Fund retained its shares of Axalta Coating Systems as Cardinal believes its earnings and cash flow will likely benefit when the supply chain untangles, pricing gains offset higher input costs, and global automobile manufacturing rebounds.

Stock selection and an underweight in the healthcare sector, particularly an underweight in biotechnology companies, were the leading contributors to performance for Cardinal’s portion of the Fund. Most biotechnology companies are not free-cash-flow-generating businesses, and their successes are often highly dependent upon a concentrated number of research projects, which led Cardinal to pass on these opportunities. Instead, shares of contract research service provider Syneos Health Inc. outpaced the healthcare sector as its free-cash-flow-generating business model permitted it to make accretive acquisitions and opportunistically repurchase shares. Cardinal’s portion of the Fund retained its shares of Syneos Health as of the end of the fiscal year in anticipation of further appreciation.

Nexstar Media Group Inc. also contributed to performance for Cardinal’s portion of the Fund for the fiscal year. Nexstar Media

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Portfolio management review
Optimum Small-Mid Cap Value Fund

outpaced other companies in the communications services sector and used its healthy free cash flow to repurchase a significant amount of stock and make an acquisition to bolster its growing media content business. Cardinal’s portion of the Fund held the shares of Nexstar at the end of the fiscal year in anticipation of potential further appreciation.

An underweight to the consumer discretionary sector likewise contributed to the performance of Cardinal’s portion of the Fund as investors increasingly became concerned about the sustainability of consumer spending levels in the face of less government stimulus and higher interest rates, as well as the expected shift within consumer spending from goods toward services.

Cardinal's portion of the Fund did not hold derivatives during the fiscal year.

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Performance summaries
Optimum Fixed Income Fund

March 31, 2022 (Unaudited)

The performance quoted represents past performance and does not guarantee future results. Investment return and principal value of an investment will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance quoted. Please obtain the performance data for the most recent month end by calling 800 914-0278 or visiting our website at optimummutualfunds.com/performance.

Expense limitations were in effect for certain classes during some or all of the periods shown in the “Fund and benchmark performance” graph. The current expenses for each class are listed on the “Fund expense ratios” table on the next page. Performance would have been lower had expense limitations not been in effect.

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

Class A shares are sold with a maximum front-end sales charge of up to 4.50%, and have an annual distribution and service fee of up to 0.25% of average daily net assets. Performance for Class A shares, excluding sales charges, assumes that no front-end sales charge applied.

Class C shares are sold with a contingent deferred sales charge of 1.00% if redeemed during the first 12 months. They are also subject to an annual distribution and service fee of up to 1.00% of average daily net assets.

Performance for Class C shares, excluding sales charges, assumes either that contingent deferred sales charges did not apply or that the investment was not redeemed.

The “Fund and benchmark performance” table and the “Performance of a $10,000 investment” graph do not reflect the deduction of taxes the shareholder would pay on Fund distributions or redemptions of Fund shares.

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Performance summaries
Optimum Fixed Income Fund

Fixed income securities and bond funds can lose value, and investors can lose principal, as interest rates rise. They also may be affected by economic conditions that hinder an issuer’s ability to make interest and principal payments on its debt. This includes prepayment risk, the risk that the principal of a bond that is held by a portfolio will be prepaid prior to maturity, at the time when interest rates are lower than what the bond was paying. A portfolio may then have to reinvest that money at a lower interest rate

High yielding, non-investment-grade bonds (junk bonds) involve higher risk than investment grade bonds. The high yield secondary market is particularly susceptible to liquidity problems when institutional investors, such as mutual funds and certain other financial institutions, temporarily stop buying bonds for regulatory, financial, or other reasons. In addition, a less liquid secondary market makes it more difficult to obtain precise valuations of the high yield securities.

Securities in the lowest of the rating categories considered to be investment grade (that is, Baa or BBB) have some speculative characteristics.

This document may mention bond ratings published by nationally recognized statistical rating organizations (NRSROs) Standard & Poor’s, Moody’s Investors Service, and Fitch, Inc. For securities rated by an NRSRO other than S&P, the rating is converted to the equivalent S&P credit rating. Bonds rated AAA are rated as having the highest quality and are generally considered to have the lowest degree of investment risk. Bonds rated AA are considered to be of high quality, but with a slightly higher degree of risk than bonds rated AAA. Bonds rated A are considered to have many favorable investment qualities, though they are somewhat more susceptible to adverse economic conditions. Bonds rated BBB are believed to be of medium-grade quality and generally riskier over the long term. Bonds rated BB, B, and CCC are regarded as having significant speculative characteristics, with BB indicating the least degree of speculation of the three.

If and when the Fund invests in forward foreign currency contracts or uses other investments to hedge against currency risks, the Fund will be subject to special risks, including counterparty risk.

The Fund may invest in derivatives, which may involve additional expenses and are subject to risk, including the risk that an underlying security or securities index moves in the opposite direction from what the portfolio manager anticipated. A derivatives transaction depends upon the counterparties’ ability to fulfill their contractual obligations.

Portfolio turnover is a measure of how frequently the managers buy and sell assets within a fund over a particular period. It is usually reported for a 12-month time period.

The disruptions caused by natural disasters, pandemics, or similar events could prevent the Fund from executing advantageous investment decisions in a timely manner and could negatively impact the Fund’s ability to achieve its investment objective and the value of the Fund’s investments.

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Performance of a $10,000 investment¹

Average annual total returns from March 31, 2012 through March 31, 2022

For period beginning March 31, 2012 through March 31, 2022			Starting value					Ending value
	Optimum Fixed Income Fund — Institutional Class shares			$	10,000				$	12,491
	Bloomberg US Aggregate Index			$	10,000				$	12,480
	Optimum Fixed Income Fund — Class A shares			$	9,550				$	11,625

The graph also assumes $10,000 invested in the Bloomberg US Aggregate Index as of March 31, 2012. The Bloomberg US Aggregate Index is a broad composite that tracks the investment grade domestic bond market.

The S&P 500 Index, mentioned on page 1, measures the performance of 500 mostly large-cap stocks weighted by market value, and is often used to represent performance of the US stock market.

The US Consumer Price Index (CPI), mentioned on page 1, is a measure of inflation that is calculated by the US Department of Labor, representing changes in prices of all goods and services purchased for consumption by urban households.

The Bloomberg US TIPS Index, mentioned on page 1, measures the total return performance of the market for inflation-protected securities issued by the US Treasury.

Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index. Past performance is not a guarantee of future results.

Performance of other Fund classes will vary due to different charges and expenses.

Stock symbols and CUSIP numbers

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Performance summaries
Optimum International Fund

March 31, 2022 (Unaudited)

The performance quoted represents past performance and does not guarantee future results. Investment return and principal value of an investment will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance quoted. Please obtain the performance data for the most recent month end by calling 800 914-0278 or visiting our website at optimummutualfunds.com/performance.

Expense limitations were in effect for certain classes during some or all of the periods shown in the “Fund and benchmark performance” graph. The current expenses for each class are listed on the “Fund expense ratios” table on the next page. Performance would have been lower had expense limitations not been in effect.

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

Class A shares are sold with a maximum front-end sales charge of up to 5.75%, and have an annual distribution and service fee of up to 0.25% of average daily net assets. Performance for Class A shares, excluding sales charges, assumes that no front-end sales charge applied.

Class C shares are sold with a contingent deferred sales charge of 1.00% if redeemed during the first 12 months. They are also subject to an annual distribution and service fee of up to 1.00% of average daily net assets.

Performance for Class C shares, excluding sales charges, assumes either that contingent deferred sales charges did not apply or that the investment was not redeemed.

The “Fund and benchmark performance” table and the “Performance of a $10,000 investment” graph do not reflect the deduction of taxes the shareholder would pay on Fund distributions or redemptions of Fund shares.

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International investments entail risks including fluctuation in currency values, differences in accounting principles, or economic or political instability. Investing in emerging markets can be riskier than investing in established foreign markets due to increased volatility, lower trading volume, and higher risk of market closures. In many emerging markets, there is substantially less publicly available information and the available information may be incomplete or misleading. Legal claims are generally more difficult to pursue.

The Fund may invest in derivatives, which may involve additional expenses and are subject to risk, including the risk that an underlying security or securities index moves in the opposite direction from what the portfolio manager anticipated. A derivatives transaction depends upon the counterparties’ ability to fulfill their contractual obligations.

There is no guarantee that dividend-paying stocks will continue to pay dividends.

The disruptions caused by natural disasters, pandemics, or similar events could prevent the Fund from executing advantageous investment decisions in a timely manner and could negatively impact the Fund’s ability to achieve its investment objective and the value of the Fund’s investments.

Performance of a $10,000 investment¹
Average annual total returns from March 31, 2012 through March 31, 2022

For period beginning March 31, 2012 through March 31, 2022			Starting value					Ending value
	MSCI ACWI ex USA Index (gross)			$	10,000				$	17,934
	MSCI ACWI ex USA Index (net)			$	10,000				$	17,168
	Optimum International Fund — Institutional Class shares			$	10,000				$	17,077
	Optimum International Fund — Class A shares			$	9,425				$	15,663

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Performance summaries
Optimum International Fund

The graph also assumes $10,000 invested in the MSCI ACWI (All Country World) ex USA Index as of March 31, 2012. The MSCI ACWI ex USA Index is a free float-adjusted market capitalization weighted index that is designed to measure equity market performance across developed and emerging markets worldwide, excluding the United States. Index “gross” return approximates the maximum possible dividend reinvestment. Index “net” return approximates the minimum possible dividend reinvestment, after deduction of withholding tax at the highest possible rate.

Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index. Past performance is not a guarantee of future results.

Performance of other Fund classes will vary due to different charges and expenses.

Stock symbols and CUSIP numbers

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Performance summaries
Optimum Large Cap Growth Fund

March 31, 2022 (Unaudited)

The performance quoted represents past performance and does not guarantee future results. Investment return and principal value of an investment will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance quoted. Please obtain the performance data for the most recent month end by calling 800 914-0278 or visiting our website at optimummutualfunds.com/performance.

Expense limitations were in effect for certain classes during some or all of the periods shown in the “Fund and benchmark performance” graph. The current expenses for each class are listed on the “Fund expense ratios” table on the next page. Performance would have been lower had expense limitations not been in effect.

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

Class A shares are sold with a maximum front-end sales charge of up to 5.75%, and have an annual distribution and service fee of up to 0.25% of average daily net assets. Performance for Class A shares, excluding sales charges, assumes that no front-end sales charge applied.

Class C shares are sold with a contingent deferred sales charge of 1.00% if redeemed during the first 12 months. They are also subject to an annual distribution and service fee of up to 1.00% of average daily net assets.

Performance for Class C shares, excluding sales charges, assumes either that contingent deferred sales charges did not apply or that the investment was not redeemed.

The “Fund and benchmark performance” table and the “Performance of a $10,000 investment” graph do not reflect the deduction of taxes the shareholder would pay on Fund distributions or redemptions of Fund shares.

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Performance summaries
Optimum Large Cap Growth Fund

REIT investments are subject to many of the risks associated with direct real estate ownership, including change in economic conditions, credit risk, and interest rate fluctuations. A REIT fund’s tax status as a regulated investment company could be jeopardized if it holds real estate directly, as a result of defaults or receive rental income from real estate holdings.

The disruptions caused by natural disasters, pandemics, or similar events could prevent the Fund from executing advantageous investment decisions in a timely manner and could negatively impact the Fund’s ability to achieve its investment objective and the value of the Fund’s investments.

Performance of a $10,000 investment¹
Average annual total returns from March 31, 2012 through March 31, 2022

For period beginning March 31, 2012 through March 31, 2022			Starting value					Ending value
	Russell 1000 Growth Index			$	10,000				$	48,238
	Optimum Large Cap Growth Fund — Institutional Class shares			$	10,000				$	39,270
	Optimum Large Cap Growth Fund — Class A shares			$	9,425				$	36,014

The graph also assumes $10,000 invested in the Russell 1000 Growth Index as of March 31, 2012. The Russell 1000 Growth Index measures the performance of the large-cap growth segment of the US equity universe. It includes those Russell 1000 companies with higher price-to-book ratios and higher forecasted growth values.

The Russell 1000 Value Index, mentioned on page 7, measures the performance of the large-cap value segment of the US equity universe. It includes those Russell 1000 companies with lower price-to-book ratios and lower forecasted growth values.

The US Consumer Price Index (CPI), mentioned on page 7, is a measure of inflation that is calculated by the US Department of Labor, representing changes in prices of all goods and services purchased for consumption by urban households.

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The S&P 500 Index, mentioned on page 7, measures the performance of 500 mostly large-cap stocks weighted by market value, and is often used to represent performance of the US stock market.

Frank Russell Company is the source and owner of the trademarks, service marks and copyrights related to the Russell Indexes. Russell^® is a trademark of Frank Russell Company.

Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index. Past performance is not a guarantee of future results.

Performance of other Fund classes will vary due to different charges and expenses.

Stock symbols and CUSIP numbers

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Performance summaries
Optimum Large Cap Value Fund

March 31, 2022 (Unaudited)

The performance quoted represents past performance and does not guarantee future results. Investment return and principal value of an investment will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance quoted. Please obtain the performance data for the most recent month end by calling 800 914-0278 or visiting our website at optimummutualfunds.com/performance.

Expense limitations were in effect for certain classes during some or all of the periods shown in the “Fund and benchmark performance” graph. The current expenses for each class are listed on the “Fund expense ratios” table on the next page. Performance would have been lower had expense limitations not been in effect.

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

Class A shares are sold with a maximum front-end sales charge of up to 5.75%, and have an annual distribution and service fee of up to 0.25% of average daily net assets. Performance for Class A shares, excluding sales charges, assumes that no front-end sales charge applied.

Class C shares are sold with a contingent deferred sales charge of 1.00% if redeemed during the first 12 months. They are also subject to an annual distribution and service fee of up to 1.00% of average daily net assets.

Performance for Class C shares, excluding sales charges, assumes either that contingent deferred sales charges did not apply or that the investment was not redeemed.

The “Fund and benchmark performance” table and the “Performance of a $10,000 investment” graph do not reflect the deduction of taxes the shareholder would pay on Fund distributions or redemptions of Fund shares.

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The disruptions caused by natural disasters, pandemics, or similar events could prevent the Fund from executing advantageous investment decisions in a timely manner and could negatively impact the Fund’s ability to achieve its investment objective and the value of the Fund’s investments.

Performance of a $10,000 investment¹

Average annual total returns from March 31, 2012 through March 31, 2022

For period beginning March 31, 2012 through March 31, 2022			Starting value					Ending value
	Russell 1000 Value Index			$	10,000				$	30,235
	Optimum Large Cap Value Fund — Institutional Class shares			$	10,000				$	26,345
	Optimum Large Cap Value Fund — Class A shares			$	9,425				$	24,165

The graph also assumes $10,000 invested in the Russell 1000 Value Index as of March 31, 2012. The Russell 1000 Value Index measures the performance of the large-cap value segment of the US equity universe. It includes those Russell 1000 companies with lower price-to-book ratios and lower forecasted growth values.

The S&P 500 Index, mentioned on page 10, measures the performance of 500 mostly large-cap stocks weighted by market value and is often used to represent performance of the US stock market.

Frank Russell Company is the source and owner of the trademarks, service marks and copyrights related to the Russell Indexes. Russell^® is a trademark of Frank Russell Company.

Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index. Past performance is not a guarantee of future results.

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Performance summaries
Optimum Large Cap Value Fund

Performance of other Fund classes will vary due to different charges and expenses.

Stock symbols and CUSIP numbers

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Performance summaries
Optimum Small-Mid Cap Growth Fund

March 31, 2022 (Unaudited)

The performance quoted represents past performance and does not guarantee future results. Investment return and principal value of an investment will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance quoted. Please obtain the performance data for the most recent month end by calling 800 914-0278 or visiting our website at optimummutualfunds.com/performance.

Expense limitations were in effect for certain classes during some or all of the periods shown in the “Fund and benchmark performance” graph. The current expenses for each class are listed on the “Fund expense ratios” table on the next page. Performance would have been lower had expense limitations not been in effect.

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

Class A shares are sold with a maximum front-end sales charge of up to 5.75%, and have an annual distribution and service fee of up to 0.25% of average daily net assets. Performance for Class A shares, excluding sales charges, assumes that no front-end sales charge applied.

Class C shares are sold with a contingent deferred sales charge of 1.00% if redeemed during the first 12 months. They are also subject to an annual distribution and service fee of up to 1.00% of average daily net assets.

Performance for Class C shares, excluding sales charges, assumes either that contingent deferred sales charges did not apply or that the investment was not redeemed.

The “Fund and benchmark performance” table and the “Performance of a $10,000 investment” graph do not reflect the deduction of taxes the shareholder would pay on Fund distributions or redemptions of Fund shares.

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Performance summaries
Optimum Small-Mid Cap Growth Fund

Investments in small and/or medium-sized companies typically exhibit greater risk and higher volatility than larger, more established companies.

The disruptions caused by natural disasters, pandemics, or similar events could prevent the Fund from executing advantageous investment decisions in a timely manner and could negatively impact the Fund’s ability to achieve its investment objective and the value of the Fund’s investments.

Performance of a $10,000 investment¹

Average annual total returns from March 31, 2012 through March 31, 2022

For period beginning March 31, 2012 through March 31, 2022			Starting value					Ending value
	Optimum Small-Mid Cap Growth Fund — Institutional Class shares			$	10,000				$	33,893
	Russell 2500 Growth Index			$	10,000				$	33,033
	Optimum Small-Mid Cap Growth Fund — Class A shares			$	9,425				$	31,118

The graph also assumes $10,000 invested in the Russell 2500 Growth Index as of March 31, 2012. The Russell 2500 Growth Index measures the performance of the small- to mid-cap growth segment of the US equity universe. It includes those Russell 2500 companies with higher price-to-book ratios and higher forecasted growth values.

Frank Russell Company is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell^® is a trademark of Frank Russell Company.

Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index. Past performance is not a guarantee of future results.

Performance of other Fund classes will vary due to different charges and expenses.

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Stock symbols and CUSIP numbers

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Performance summaries
Optimum Small-Mid Cap Value Fund

March 31, 2022 (Unaudited)

The performance quoted represents past performance and does not guarantee future results. Investment return and principal value of an investment will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance quoted. Please obtain the performance data for the most recent month end by calling 800 914-0278 or visiting our website at optimummutualfunds.com/performance.

Expense limitations were in effect for certain classes during some or all of the periods shown in the “Fund and benchmark performance” graph. The current expenses for each class are listed on the “Fund expense ratios” table on the next page. Performance would have been lower had expense limitations not been in effect.

Institutional Class shares are not subject to a sales charge and are offered for sale exclusively to certain eligible investors. In addition, Institutional Class shares pay no distribution and service fee.

Class A shares are sold with a maximum front-end sales charge of up to 5.75%, and have an annual distribution and service fee of up to 0.25% of average daily net assets. Performance for Class A shares, excluding sales charges, assumes that no front-end sales charge applied.

Class C shares are sold with a contingent deferred sales charge of 1.00% if redeemed during the first 12 months. They are also subject to an annual distribution and service fee of up to 1.00% of average daily net assets.

Performance for Class C shares, excluding sales charges, assumes either that contingent deferred sales charges did not apply or that the investment was not redeemed.

The “Fund and benchmark performance” table and the “Performance of a $10,000 investment” graph do not reflect the deduction of taxes the shareholder would pay on Fund distributions or redemptions of Fund shares.

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Investments in small and/or medium-sized companies typically exhibit greater risk and higher volatility than larger, more established companies.

The disruptions caused by natural disasters, pandemics, or similar events could prevent the Fund from executing advantageous investment decisions in a timely manner and could negatively impact the Fund’s ability to achieve its investment objective and the value of the Fund’s investments.

Performance of a $10,000 investment¹

Average annual total returns from March 31, 2012 through March 31, 2022

For period beginning March 31, 2012 through March 31, 2022			Starting value					Ending value
	Russell 2500 Value Index			$	10,000				$	28,498
	Optimum Small-Mid Cap Value Fund — Institutional Class shares			$	10,000				$	20,978
	Optimum Small-Mid Cap Value Fund — Class A shares			$	9,425				$	19,256

The graph also assumes $10,000 invested in the Russell 2500 Value Index as of March 31, 2012. The Russell 2500 Value Index measures the performance of the small- to mid-cap value segment of the US equity universe. It includes those Russell 2500 companies with lower price-to-book ratios and lower forecasted growth values.

The S&P 500 Index, mentioned on page 16, measures the performance of 500 mostly large-cap stocks weighted by market value, and is often used to represent performance of the US stock market.

The Russell 2500 Growth Index, mentioned on page 16, measures the performance of the small- to mid-cap growth segment of the US equity universe. It includes those Russell 2500 companies with higher price-to-book ratios and higher forecasted growth values.

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Performance summaries
Optimum Small-Mid Cap Value Fund

Frank Russell Company is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell^® is a trademark of Frank Russell Company.

Index performance returns do not reflect any management fees, transaction costs, or expenses. Indices are unmanaged and one cannot invest directly in an index. Past performance is not a guarantee of future results.

Performance of other Fund classes will vary due to different charges and expenses.

Stock symbols and CUSIP numbers

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Disclosure of Fund expenses
For the six-month period from October 1, 2021 to March 31, 2022 (Unaudited)

As a shareholder of a Fund, you incur two types of costs: (1) transaction costs, including sales charges (loads) on purchase payments, reinvested dividends, or other distributions; redemption fees; and exchange fees; and (2) ongoing costs, including management fees; distribution and service (12b-1) fees; and other Fund expenses. The following examples are intended to help you understand your ongoing costs (in dollars) of investing in a Fund and to compare these costs with the ongoing costs of investing in other mutual funds.

The examples are based on an investment of $1,000 invested at the beginning of the period and held for the entire six-month period from October 1, 2021 to March 31, 2022.

Actual Expenses

The first section of the tables shown, “Actual Fund return,” provides information about actual account values and actual expenses. You may use the information in this section of the table, together with the amount you invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the result by the number in the first section under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Hypothetical Example for Comparison Purposes

The second section of the tables shown, “Hypothetical 5% return,” provides information about hypothetical account values and hypothetical expenses based on the Funds' actual expense ratios and an assumed rate of return of 5% per year before expenses, which is not the Funds' actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare the ongoing costs of investing in each Fund and other funds. To do so, compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of the other funds.

Please note that the expenses shown in the tables are meant to highlight your ongoing costs only and do not reflect any transactional costs, such as sales charges (loads), redemption fees, or exchange fees. Therefore, the second section of each table is useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds. In addition, if these transactional costs were included, your costs would have been higher. The Funds’ expenses shown in the tables reflect fee waivers in effect and assume reinvestment of all dividends and distributions.

Optimum Fixed Income Fund
Expense analysis of an investment of $1,000

Optimum International Fund
Expense analysis of an investment of $1,000

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Disclosure of Fund expenses

Optimum Large Cap Growth Fund
Expense analysis of an investment of $1,000

Optimum Large Cap Value Fund
Expense analysis of an investment of $1,000

Optimum Small-Mid Cap Growth Fund
Expense analysis of an investment of $1,000

Optimum Small-Mid Cap Value Fund
Expense analysis of an investment of $1,000

In addition to the Funds' expenses reflected above and on the previous page, each Fund also indirectly bears its portion of the fees and expenses of any investment companies (Underlying Funds) in which it invests. The tables above and on the previous page do not reflect the expenses of any applicable Underlying Funds.

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Security type / sector allocations
Optimum Fixed Income Fund

As of March 31, 2022 (Unaudited)

Sector designations may be different from the sector designations presented in other Fund materials. The sector designations may represent the investment manager or sub-advisor’s internal sector classifications, which may result in the sector designations for one fund being different from another fund’s sector designations.

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Security type / sector and country allocations
Optimum International Fund

As of March 31, 2022 (Unaudited)

Sector designations may be different from the sector designations presented in other Fund materials. The sector designations may represent the investment manager or sub-advisor’s internal sector classifications, which may result in the sector designations for one fund being different from another fund’s sector designations.

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Security type / sector allocations and top 10 equity holdings
Optimum Large Cap Growth Fund

As of March 31, 2022 (Unaudited)

Sector designations may be different from the sector designations presented in other Fund materials. The sector designations may represent the investment manager or sub-advisor’s internal sector classifications, which may result in the sector designations for one fund being different from another fund’s sector designations.

Holdings are for informational purposes only and are subject to change at any time. They are not a recommendation to buy, sell, or hold any security.

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Security type / sector allocations and top 10 equity holdings
Optimum Large Cap Value Fund

As of March 31, 2022 (Unaudited)

Sector designations may be different from the sector designations presented in other Fund materials. The sector designations may represent the investment manager or sub-advisor’s internal sector classifications, which may result in the sector designations for one fund being different from another fund’s sector designations.

Holdings are for informational purposes only and are subject to change at any time. They are not a recommendation to buy, sell, or hold any security.

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Security type / sector allocations and top 10 equity holdings
Optimum Small-Mid Cap Growth Fund

As of March 31, 2022 (Unaudited)

Sector designations may be different from the sector designations presented in other Fund materials. The sector designations may represent the investment manager or sub-advisor’s internal sector classifications, which may result in the sector designations for one fund being different from another fund’s sector designations.

Holdings are for informational purposes only and are subject to change at any time. They are not a recommendation to buy, sell, or hold any security.

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Security type / sector allocations and top 10 equity holdings
Optimum Small-Mid Cap Value Fund

As of March 31, 2022 (Unaudited)

Sector designations may be different from the sector designations presented in other Fund materials. The sector designations may represent the investment manager or sub-advisor’s internal sector classifications, which may result in the sector designations for one fund being different from another fund’s sector designations.

Holdings are for informational purposes only and are subject to change at any time. They are not a recommendation to buy, sell, or hold any security.

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Schedules of investments
Optimum Fixed Income Fund

March 31, 2022

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Schedules of investments
Optimum Fixed Income Fund