American Funds Capital Income Builder (CAIBX) N-CSRSCertified semi-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

Investment Company Act File Number: 811-05085

Capital Income Builder

(Exact Name of Registrant as Specified in Charter)

333 South Hope Street

Los Angeles, California 90071

(Address of Principal Executive Offices)

Registrant's telephone number, including area code: (949) 975-5000

Date of fiscal year end: October 31

Date of reporting period: April 30, 2020

Gregory F. Niland

Capital Income Builder

5300 Robin Hood Road

Norfolk, Virginia 23513

(Name and Address of Agent for Service)

ITEM 1 – Reports to Stockholders

Capital Income Builder®   Semi-annual report for the six months ended April 30, 2020

Seeking income
growth opportunities
from around
the world

Beginning January 1, 2021, as permitted by regulations adopted by the U.S. Securities and Exchange Commission, we intend to no longer mail paper copies of the fund’s shareholder reports, unless specifically requested from American Funds or your financial intermediary, such as a broker-dealer or bank. Instead, the reports will be made available on the Capital Group website (capitalgroup.com); you will be notified by mail and provided with a website link to access the report each time a report is posted. If you have already elected to receive shareholder reports electronically, you will not be affected by this change and do not need to take any action. If you prefer to receive shareholder reports and other communications electronically, you may update your mailing preferences with your financial intermediary, or enroll in e-delivery at capitalgroup.com (for accounts held directly with the fund).

You may elect to receive paper copies of all future reports free of charge. If you invest through a financial intermediary, you may contact your financial intermediary to request that you continue to receive paper copies of your shareholder reports. If you invest directly with the fund, you may inform American Funds that you wish to continue receiving paper copies of your shareholder reports by contacting us at (800) 421-4225. Your election to receive paper reports will apply to all funds held with American Funds or through your financial intermediary.

Capital Income Builder seeks to provide you with a level of current income that exceeds the average yield on U.S. stocks generally and to provide you with a growing stream of income over the years. The fund’s secondary objective is to provide you with growth of capital.

This fund is one of more than 40 offered by Capital Group, home of American Funds, one of the nation’s largest mutual fund families. For nearly 90 years, Capital has invested with a long-term focus based on thorough research and attention to risk.

Fund results shown in this report, unless otherwise indicated, are for Class A shares at net asset value. If a sales charge (maximum 5.75%) had been deducted, the results would have been lower. Results are for past periods and are not predictive of results for future periods. Current and future results may be lower or higher than those shown. Prices and returns will vary, so investors may lose money. Investing for short periods makes losses more likely. For current information and month-end results, visit capitalgroup.com.

Here are the average annual total returns on a $1,000 investment with all distributions reinvested for periods ended March 31, 2020 (the most recent calendar quarter-end):

For other share class results, visit capitalgroup.com and americanfundsretirement.com.

The total annual fund operating expense ratio was 0.61% for Class A shares as of the prospectus dated January 1, 2020. The expense ratio is restated to reflect current fees.

Investment results assume all distributions are reinvested and reflect applicable fees and expenses. When applicable, investment results reflect fee waivers, without which results would have been lower. Visit capitalgroup.com for more information.

The fund’s 30-day yield for Class A shares as of May 31, 2020, reflecting the 5.75% maximum sales charge and calculated in accordance with the U.S. Securities and Exchange Commission formula, was 2.70%.

The return of principal for bond funds and for funds with significant underlying bond holdings is not guaranteed. Fund shares are subject to the same interest rate, inflation and credit risks associated with the underlying bond holdings. Investing outside the United States may be subject to additional risks, such as currency fluctuations, periods of illiquidity and price volatility. These risks may be heightened in connection with investments in developing countries. Refer to the fund prospectus and the Risk Factors section of this report for more information on these and other risks associated with investing in the fund.

Investments are not FDIC-insured, nor are they deposits of or guaranteed by a bank or any other entity, so they may lose value.

Fellow investors:

Shown in the table below are Capital Income Builder’s results for the six months ended April 30, 2020. Also shown are the results of its primary and secondary benchmarks, and its Lipper peer group.

For additional information about the fund, its investment results, holdings and portfolio managers, visit capitalgroup.com/individual/investments/fund/CAIBX. You can also access information about Capital Group’s American Funds and read our insights about the markets, retirement, saving for college, investing fundamentals and more atcapitalgroup.com.

Results at a glance

For periods ended April 30, 2020, with all distributions reinvested

This summary investment portfolio is designed to streamline the report and help investors better focus on the fund’s principal holdings. See the inside back cover for details on how to obtain a complete schedule of portfolio holdings.

“Other securities” includes all issues that are not disclosed separately in the summary investment portfolio. “Other securities” also includes loan participations and assignments, which may be subject to legal or contractual restrictions on resale. The total value of all such loans was $88,000, which represented less than .01% of the net assets of the fund. “Other securities” also includes securities on loan. The total value of securities on loan was $165,847,000, which represented .18% of the net assets of the fund. Refer to Note 5 for more information on securities lending.

Futures contracts

Forward currency contracts

Swap contracts

Interest rate swaps

Swap contracts(continued)

Interest rate swaps(continued)

Investments in affiliates

A company is an affiliate of the fund under the Investment Company Act of 1940 if the fund’s holdings represent 5% or more of the outstanding voting shares of that company. The value of the fund’s affiliated-company holdings is either shown in the summary investment portfolio or included in the value of “Other securities” under the respective industry sectors. Further details on these holdings and related transactions during the six months ended April 30, 2020, appear below.

The following footnotes apply to either the individual securities noted or one or more of the securities aggregated and listed as a single line item.

Key to abbreviations and symbol

ADR = American Depositary Receipts

CAD = Canadian dollars

EFFR = Effective Federal Funds Rate

EUR = Euros

LIBOR = London Interbank Offered Rate

TBA = To-be-announced

USD/$ = U.S. dollars

See notes to financial statements.

Financial statements

See notes to financial statements.

(dollars and shares in thousands, except per-share amounts)

Shares of beneficial interest issued and outstanding (no stated par value) —
unlimited shares authorized (1,687,335 total shares outstanding)

See notes to financial statements.

See notes to financial statements.

See notes to financial statements.

1. Organization

Capital Income Builder (the “fund”) is registered under the Investment Company Act of 1940 as an open-end, diversified management investment company. The fund seeks to provide a level of current income that exceeds the average yield on U.S. stocks generally and a growing stream of income over the years. Growth of capital is a secondary objective.

The fund has 19 share classes consisting of six retail share classes (Classes A, C, T, F-1, F-2 and F-3), five 529 college savings plan share classes (Classes 529-A, 529-C, 529-E, 529-T and 529-F-1) and eight retirement plan share classes (Classes R-1, R-2, R-2E, R-3, R-4, R-5E, R-5 and R-6). The 529 college savings plan share classes can be used to save for college education. The retirement plan share classes are generally offered only through eligible employer-sponsored retirement plans. The fund’s share classes are described further in the following table:

Holders of all share classes have equal pro rata rights to the assets, dividends and liquidation proceeds of the fund. Each share class has identical voting rights, except for the exclusive right to vote on matters affecting only its class. Share classes have different fees and expenses (“class-specific fees and expenses”), primarily due to different arrangements for distribution, transfer agent and administrative services. Differences in class-specific fees and expenses will result in differences in net investment income and, therefore, the payment of different per-share dividends by each share class.

2. Significant accounting policies

The fund is an investment company that applies the accounting and reporting guidance issued in Topic 946 by the U.S. Financial Accounting Standards Board. The fund’s financial statements have been prepared to comply with U.S. generally accepted accounting principles (“U.S. GAAP”). These principles require the fund’s investment adviser to make estimates and assumptions that affect reported amounts and disclosures. Actual results could differ from those estimates. Subsequent events, if any, have been evaluated through the date of issuance in the preparation of the financial statements. The fund follows the significant accounting policies described in this section, as well as the valuation policies described in the next section on valuation.

Security transactions and related investment income — Security transactions are recorded by the fund as of the date the trades are executed with brokers. Realized gains and losses from security transactions are determined based on the specific identified cost of the securities. In the event a security is purchased with a delayed payment date, the fund will segregate liquid assets sufficient to meet its payment obligations. Dividend income is recognized on the ex-dividend date and interest income is recognized on an accrual basis. Market discounts, premiums and original issue discounts on fixed-income securities are amortized daily over the expected life of the security.

Class allocations — Income, fees and expenses (other than class-specific fees and expenses), realized gains and losses and unrealized appreciation and depreciation are allocated daily among the various share classes based on their relative net assets. Class-specific fees and expenses, such as distribution, transfer agent and administrative services, are charged directly to the respective share class.

Distributions paid to shareholders — Income dividends and capital gain distributions are recorded on the ex-dividend date.

Currency translation — Assets and liabilities, including investment securities, denominated in currencies other than U.S. dollars are translated into U.S. dollars at the exchange rates supplied by one or more pricing vendors on the valuation date. Purchases and sales of investment securities and income and expenses are translated into U.S. dollars at the exchange rates on the dates of such transactions. The effects of changes in exchange rates on investment securities are included with the net realized gain or loss and net unrealized appreciation or depreciation on investments in the fund’s statement of operations. The realized gain or loss and unrealized appreciation or depreciation resulting from all other transactions denominated in currencies other than U.S. dollars are disclosed separately.

3. Valuation

Capital Research and Management Company (“CRMC”), the fund’s investment adviser, values the fund’s investments at fair value as defined by U.S. GAAP. The net asset value of each share class of the fund is generally determined as of approximately 4:00 p.m. New York time each day the New York Stock Exchange is open.

Methods and inputs — The fund’s investment adviser uses the following methods and inputs to establish the fair value of the fund’s assets and liabilities. Use of particular methods and inputs may vary over time based on availability and relevance as market and economic conditions evolve.

Equity securities are generally valued at the official closing price of, or the last reported sale price on, the exchange or market on which such securities are traded, as of the close of business on the day the securities are being valued or, lacking any sales, at the last available bid price. Prices for each security are taken from the principal exchange or market on which the security trades.

Fixed-income securities, including short-term securities, are generally valued at prices obtained from one or more pricing vendors. Vendors value such securities based on one or more of the inputs described in the following table. The table provides examples of inputs that are commonly relevant for valuing particular classes of fixed-income securities in which the fund is authorized to invest. However, these classifications are not exclusive, and any of the inputs may be used to value any other class of fixed-income security.

When the fund’s investment adviser deems it appropriate to do so (such as when vendor prices are unavailable or deemed to be not representative), fixed-income securities will be valued in good faith at the mean quoted bid and ask prices that are reasonably and timely available (or bid prices, if ask prices are not available) or at prices for securities of comparable maturity, quality and type.

Securities with both fixed-income and equity characteristics, or equity securities traded principally among fixed-income dealers, are generally valued in the manner described for either equity or fixed-income securities, depending on which method is deemed most appropriate by the fund’s investment adviser. The Capital Group Central Cash Fund (“CCF”), a fund within the Capital Group Central Fund Series (“Central Funds”), is valued based upon a floating net asset value, which fluctuates with changes in the value of CCF’s portfolio securities. The underlying securities are valued based on the policies and procedures in CCF’s statement of additional information. Exchange-traded futures are generally valued at the official settlement price of the exchange or market on which such instruments are traded, as of the close of business on the day the futures are being valued. Forward currency contracts are valued at the mean of representative quoted bid and ask prices, generally based on prices supplied by one or more pricing vendors. Interest rate swaps are generally valued by pricing vendors based on market inputs that include the index and term of index, reset frequency, payer/receiver, currency and pay frequency.

Securities and other assets for which representative market quotations are not readily available or are considered unreliable by the fund’s investment adviser are fair valued as determined in good faith under fair valuation guidelines adopted by authority of the fund’s board of trustees as further described. The investment adviser follows fair valuation guidelines, consistent with U.S. Securities and Exchange Commission rules and guidance, to consider relevant principles and factors when making fair value determinations. The investment adviser considers relevant indications of value that are reasonably and timely available to it in determining the fair value to be assigned to a particular security, such as the type and cost of the security; contractual or legal restrictions on resale of the security; relevant financial or business developments of the issuer; actively traded similar or related securities; conversion or exchange rights on the security; related corporate actions; significant events occurring after the close of trading in the security; and changes in overall market conditions. In addition, the closing prices of equity securities that trade in markets outside U.S. time zones may be adjusted to reflect significant events that occur after the close of local trading but before the net asset value of each share class of the fund is determined. Fair valuations and valuations of investments that are not actively trading involve judgment and may differ materially from valuations that would have been used had greater market activity occurred.

Processes and structure — The fund’s board of trustees has delegated authority to the fund’s investment adviser to make fair value determinations, subject to board oversight. The investment adviser has established a Joint Fair Valuation Committee (the “Fair Valuation Committee”) to administer, implement and oversee the fair valuation process, and to make fair value decisions. The Fair Valuation Committee regularly reviews its own fair value decisions, as well as decisions made under its standing instructions to the investment adviser’s valuation teams. The Fair Valuation Committee reviews changes in fair value measurements from period to period and may, as deemed appropriate, update the fair valuation guidelines to better reflect the results of back testing and address new or evolving issues. The Fair Valuation Committee reports any changes to the fair valuation guidelines to the board of trustees. The fund’s board and audit committee also regularly review reports that describe fair value determinations and methods.

The fund’s investment adviser has also established a Fixed-Income Pricing Review Group to administer and oversee the fixed-income valuation process, including the use of fixed-income pricing vendors. This group regularly reviews pricing vendor information and market data. Pricing decisions, processes and controls over security valuation are also subject to additional internal reviews, including an annual control self-evaluation program facilitated by the investment adviser’s compliance group.

Classifications — The fund’s investment adviser classifies the fund’s assets and liabilities into three levels based on the inputs used to value the assets or liabilities. Level 1 values are based on quoted prices in active markets for identical securities. Level 2 values are based on significant observable market inputs, such as quoted prices for similar securities and quoted prices in inactive markets. Certain securities trading outside the U.S. may transfer between Level 1 and Level 2 due to valuation adjustments resulting from significant market movements following the close of local trading. Level 3 values are based on significant unobservable inputs that reflect the investment adviser’s determination of assumptions that market participants might reasonably use in valuing the securities. The valuation levels are not necessarily an indication of the risk or liquidity associated with the underlying investment. For example, U.S. government securities are reflected as Level 2 because the inputs used to determine fair value may not always be quoted prices in an active market.

The following tables present the fund’s valuation levels as of April 30, 2020 (dollars in thousands):

4. Risk factors

Investing in the fund may involve certain risks including, but not limited to, those described below.

Market conditions — The prices of, and the income generated by, the common stocks, bonds and other securities held by the fund may decline — sometimes rapidly or unpredictably — due to various factors, including events or conditions affecting the general economy or particular industries; overall market changes; local, regional or global political, social or economic instability; governmental, governmental agency or central bank responses to economic conditions; and currency exchange rate, interest rate and commodity price fluctuations. These risks may be heightened in the case of smaller capitalization stocks.

Issuer risks — The prices of, and the income generated by, securities held by the fund may decline in response to various factors directly related to the issuers of such securities, including reduced demand for an issuer’s goods or services, poor management performance, major litigation related to the issuer, changes in government regulations affecting the issuer or its competitive environment and strategic initiatives such as mergers, acquisitions or dispositions and the market response to any such initiatives.

Investing in income-oriented stocks — The value of the fund’s securities and income provided by the fund may be reduced by changes in the dividend policies of, and the capital resources available for dividend payments at, the companies in which the fund invests.

Investing in debt instruments — The prices of, and the income generated by, bonds and other debt securities held by the fund may be affected by changing interest rates and by changes in the effective maturities and credit ratings of these securities.

Rising interest rates will generally cause the prices of bonds and other debt securities to fall. A general rise in interest rates may cause investors to sell debt securities on a large scale, which could also adversely affect the price and liquidity of debt securities and could also result in increased redemptions from the fund. Falling interest rates may cause an issuer to redeem, call or refinance a debt security before its stated maturity, which may result in the fund failing to recoup the full amount of its initial investment and having to reinvest the proceeds in lower yielding securities. Longer maturity debt securities generally have greater sensitivity to changes in interest rates and may be subject to greater price fluctuations than shorter maturity debt securities.

Bonds and other debt securities are also subject to credit risk, which is the possibility that the credit strength of an issuer or guarantor will weaken or be perceived to be weaker, and/or an issuer of a debt security will fail to make timely payments of principal or interest and the security will go into default. A downgrade or default affecting any of the fund’s securities could cause the value of the fund’s shares to decrease. Lower quality debt securities generally have higher rates of interest and may be subject to greater price

fluctuations than higher quality debt securities. Credit risk is gauged, in part, by the credit ratings of the debt securities in which the fund invests. However, ratings are only the opinions of the rating agencies issuing them and are not guarantees as to credit quality or an evaluation of market risk. The fund’s investment adviser relies on its own credit analysts to research issuers and issues in seeking to assess credit and default risks.

Investing outside the U.S. — Securities of issuers domiciled outside the U.S., or with significant operations or revenues outside the U.S., may lose value because of adverse political, social, economic or market developments (including social instability, regional conflicts, terrorism and war) in the countries or regions in which the issuers operate or generate revenue. These securities may also lose value due to changes in foreign currency exchange rates against the U.S. dollar and/or currencies of other countries. Issuers of these securities may be more susceptible to actions of foreign governments, such as nationalization, currency blockage or the imposition of price controls or punitive taxes, each of which could adversely impact the value of these securities. Securities markets in certain countries may be more volatile and/or less liquid than those in the U.S. Investments outside the U.S. may also be subject to different accounting practices and different regulatory, legal and reporting standards and practices, and may be more difficult to value, than those in the U.S. In addition, the value of investments outside the U.S. may be reduced by foreign taxes, including foreign withholding taxes on interest and dividends. Further, there may be increased risks of delayed settlement of securities purchased or sold by the fund. The risks of investing outside the U.S. may be heightened in connection with investments in emerging markets.

Management — The investment adviser to the fund actively manages the fund’s investments. Consequently, the fund is subject to the risk that the methods and analyses, including models, tools and data, employed by the investment adviser in this process may be flawed or incorrect and may not produce the desired results. This could cause the fund to lose value or its investment results to lag relevant benchmarks or other funds with similar objectives.

5. Certain investment techniques

Securities lending — The fund has entered into securities lending transactions in which the fund earns income by lending investment securities to brokers, dealers or other institutions. Each transaction involves three parties: the fund, acting as the lender of the securities, a borrower, and a lending agent that acts as an intermediary.

Securities lending transactions are entered into by the fund under a securities lending agent agreement with the lending agent. The lending agent facilitates the exchange of securities between the lender and approved borrowers, ensures that securities loans are properly coordinated and documented, marks-to-market the value of collateral daily, secures additional collateral from a borrower if it falls below preset terms, and may reinvest cash collateral on behalf of the fund according to agreed parameters. The lending agent provides indemnification to the fund against losses resulting from a borrower default. Although risk is mitigated by the collateral and indemnification, the

fund could experience a delay in recovering its securities and a potential loss of income or value if a borrower fails to return securities, collateral investments decline in value or the lending agent fails to perform.

The borrower is required to post highly liquid assets, such as cash or U.S. government securities, as collateral for the loan in an amount at least equal to the value of the securities loaned. Investments made with cash collateral are recognized as assets in the fund’s investment portfolio. The same amount is recorded as a liability in the fund’s statement of assets and liabilities. While securities are on loan, the fund will continue to receive the equivalent of the interest, dividends or other distributions paid by the issuer, as well as a portion of the interest on the investment of the collateral. Additionally, although the fund does not have the right to vote on securities while they are on loan, the fund has a right to consent on corporate actions and a right to recall loaned securities to vote. A borrower is obligated to return loaned securities at the conclusion of a loan or, during the pendency of a loan, on demand from the fund.

As of April 30, 2020, the total value of securities on loan was $165,847,000, and the total value of collateral received was $174,270,000. Collateral received includes cash of $11,290,000 and U.S. government securities of $162,980,000. Investment securities purchased from cash collateral of $11,290,000 are disclosed in the summary investment portfolio as short-term securities. Securities received as collateral, if any, are not recognized as fund assets. The contractual maturity of cash collateral received under the securities lending agreement is classified as overnight and continuous.

Index-linked bonds — The fund has invested in index-linked bonds, which are fixed-income securities whose principal value is periodically adjusted to a government price index. Over the life of an index-linked bond, interest is paid on the adjusted principal value. Increases or decreases in the principal value of index-linked bonds are recorded as interest income in the fund’s statement of operations.

Mortgage dollar rolls — The fund has entered into mortgage dollar roll transactions in which the fund sells a mortgage-backed security to a counterparty and simultaneously enters into an agreement with the same counterparty to buy back a similar security on a specific future date at a predetermined price. Mortgage dollar rolls are accounted for as purchase and sale transactions. Portfolio turnover rates excluding and including mortgage dollar rolls are presented at the end of the fund’s financial highlights table.

Loan transactions — The fund has entered into loan transactions in which the fund acquires a loan either through an agent, by assignment from another holder, or as a participation interest in another holder’s portion of a loan. The loan is often administered by a financial institution that acts as agent for the holders of the loan, and the fund may be required to receive approval from the agent and/or borrower prior to the sale of the investment. The loan’s interest rate and maturity date may change based on the terms of the loan, including potential early payments of principal.

Futures contracts — The fund has entered into futures contracts, which provide for the future sale by one party and purchase by another party of a specified amount of a specific financial instrument for a specified price, date, time and place designated at the time the contract is made. Futures contracts are used to strategically manage the fund’s interest rate sensitivity by increasing or decreasing the duration of the fund or a portion of the fund’s portfolio.

Upon entering into futures contracts, and to maintain the fund’s open positions in futures contracts, the fund is required to deposit with a futures broker, known as a futures commission merchant (“FCM”), in a segregated account in the name of the FCM an amount of cash, U.S. government securities or other liquid securities, known as initial margin. The margin required for a particular futures contract is set by the exchange on which the contract is traded to serve as collateral, and may be significantly modified from time to time by the exchange during the term of the contract.

On a daily basis, the fund pays or receives variation margin based on the increase or decrease in the value of the futures contracts and records variation margin on futures contracts in the statement of assets and liabilities. In addition, the fund segregates liquid assets equivalent to the fund’s outstanding obligations under the contract in excess of the initial margin and variation margin, if any. Futures contracts may involve a risk of loss in excess of the variation margin shown on the fund’s statement of assets and liabilities. The fund records realized gains or losses at the time the futures contract is closed or expires. Net realized gains or losses and net unrealized appreciation or depreciation from futures contracts are recorded in the fund’s statement of operations. The average month-end notional amount of futures contracts while held was $10,972,367,000.

Forward currency contracts — The fund has entered into forward currency contracts, which represent agreements to exchange currencies on specific future dates at predetermined rates. The fund’s investment adviser uses forward currency contracts to manage the fund’s exposure to changes in exchange rates. Upon entering into these contracts, risks may arise from the potential inability of counterparties to meet the terms of their contracts and from possible movements in exchange rates.

On a daily basis, the fund’s investment adviser values forward currency contracts and records unrealized appreciation or depreciation for open forward currency contracts in the fund’s statement of assets and liabilities. Realized gains or losses are recorded at the time the forward currency contract is closed or offset by another contract with the same broker for the same settlement date and currency.

Closed forward currency contracts that have not reached their settlement date are included in the respective receivables or payables for closed forward currency contracts in the fund’s statement of assets and liabilities. Net realized gains or losses from closed forward currency contracts and net unrealized appreciation or depreciation from open forward currency contracts are recorded in the fund’s statement of operations. The average month-end notional amount of open forward currency contracts while held was $84,596,000.

Interest rate swaps — The fund has entered into interest rate swap contracts, which are agreements to exchange one stream of future interest payments for another based on a specified notional amount. Typically, interest rate swaps exchange a fixed interest rate for a payment that floats relative to a benchmark or vice versa. The fund’s investment adviser uses interest rate swaps to seek to manage the interest rate sensitivity of the fund by increasing or decreasing the duration of the fund or a portion of the fund’s portfolio. Risks may arise as a result of the fund’s investment adviser incorrectly anticipating changes in interest rates, increased volatility, reduced liquidity and the potential inability of counterparties to meet the terms of their agreements.

Upon entering into an interest rate swap contract, the fund is required to deposit cash, U.S. government securities or other liquid securities, which is known as initial margin. Generally, the initial margin required for a particular interest rate swap is set and held as collateral by the clearinghouse on which the contract is cleared. The amount of initial margin required may be significantly modified from time to time by the clearinghouse during the term of the contract.

On a daily basis, the fund’s investment adviser records daily interest accruals related to the exchange of future payments as a receivable and payable in the fund’s statement of assets and liabilities. The fund also pays or receives a variation margin based on the increase or decrease in the value of the interest rate swaps, including accrued interest, and records variation margin on interest rate swaps in the statement of assets and liabilities. The fund records realized gains and losses on both the net accrued interest and any gain or loss recognized at the time the interest rate swap is closed or expires. Net realized gains or losses, as well as any net unrealized appreciation or depreciation, from interest rate swaps are recorded in the fund’s statement of operations. The average month-end notional amount of interest rate swaps while held was $28,028,017,000.

The following tables identify the location and fair value amounts on the fund’s statement of assets and liabilities and the effect on the fund’s statement of operations resulting from the fund’s use of futures contracts, forward currency contracts and interest rate swaps as of, or for the six months ended, April 30, 2020 (dollars in thousands):

See end of tables for footnote.

Collateral — The fund participates in a collateral program due to securities lending and its use of futures contracts, forward currency contracts, interest rate swaps and future delivery contracts. For securities lending, the fund receives collateral in exchange for lending investment securities. The purpose of the collateral is to cover potential losses that could occur in the event that the borrower cannot meet its contractual obligation. The lending agent may reinvest cash collateral from securities lending transactions according to agreed parameters. Cash collateral reinvested by the lending agent, if any, is disclosed in the fund’s summary investment portfolio. For futures contracts and interest rate swaps, the fund pledges collateral for initial and variation margin by contract. For forward currency contracts, the fund either receives or pledges collateral based on the net gain or loss on unsettled forward currency contracts by counterparty. For future delivery contracts, the fund either receives or pledges collateral based on the net gain or loss on unsettled contracts by certain counterparties. The purpose of the collateral is to cover potential losses that could occur in the event that either party cannot meet its contractual obligation. Non-cash collateral pledged by the fund, if any, is disclosed in the fund’s investment portfolio, and cash collateral pledged by the fund, if any, is held in a segregated account with the fund’s custodian, which is reflected as pledged cash collateral in the fund’s statement of assets and liabilities.

Rights of offset — The fund has entered into enforceable master netting agreements with certain counterparties for forward currency contracts, where on any date amounts payable by each party to the other (in the same currency with respect to the same transaction) may be closed or offset by each party’s payment obligation. If an early termination date occurs under these agreements following an event of default or termination event, all obligations of each party to its counterparty are settled net through a single payment in a single currency (“close-out netting”). For financial reporting purposes, the fund does not offset financial assets and financial liabilities that are subject to these master netting arrangements in the statement of assets and liabilities.

The following table presents the fund’s forward currency contracts by counterparty that are subject to master netting agreements but that are not offset in the fund’s statement of assets and liabilities. The net amount column shows the impact of offsetting on the fund’s statement of assets and liabilities as of April 30, 2020, if close-out netting was exercised (dollars in thousands):

6. Taxation and distributions

Federal income taxation — The fund complies with the requirements under Subchapter M of the Internal Revenue Code applicable to mutual funds and intends to distribute substantially all of its net taxable income and net capital gains each year. The fund is not subject to income taxes to the extent such distributions are made. Therefore, no federal income tax provision is required.

As of and during the period ended April 30, 2020, the fund did not have a liability for any unrecognized tax benefits. The fund recognizes interest and penalties, if any, related to unrecognized tax benefits as income tax expense in the statement of operations. During the period, the fund did not incur any significant interest or penalties.

The fund’s tax returns are not subject to examination by federal, state and, if applicable, non-U.S. tax authorities after the expiration of each jurisdiction’s statute of limitations, which is generally three years after the date of filing but can be extended in certain jurisdictions.

Non-U.S. taxation — Dividend and interest income are recorded net of non-U.S. taxes paid. The fund may file withholding tax reclaims in certain jurisdictions to recover a portion of amounts previously withheld. As a result of rulings from European courts, the fund filed for additional reclaims related to prior years. These reclaims are recorded when the amount is known and there are no significant uncertainties on collectability. Gains realized by the fund on the sale of securities in certain countries, if any, may be subject to non-U.S. taxes. If applicable, the fund records an estimated deferred tax liability based on unrealized gains to provide for potential non-U.S. taxes payable upon the sale of these securities.

Distributions — Distributions paid to shareholders are based on net investment income and net realized gains determined on a tax basis, which may differ from net investment income and net realized gains for financial reporting purposes. These differences are due primarily to different treatment for items such as currency gains and losses; short-term capital gains and losses; capital losses related to sales of certain securities within 30 days of purchase; unrealized appreciation of certain investments in securities outside the U.S.; cost of investments sold; paydowns on fixed-income securities; amortization of premiums and discounts and income on certain investments. The fiscal year in which amounts are distributed may differ from the year in which the net investment income and net realized gains are recorded by the fund for financial reporting purposes.

The components of distributable earnings on a tax basis are reported as of the fund’s most recent year-end. As of October 31, 2019, the components of distributable earnings on a tax basis were as follows (dollars in thousands):

As of April 30, 2020, the tax basis unrealized appreciation (depreciation) and cost of investments were as follows (dollars in thousands):

Distributions paid were characterized for tax purposes as follows (dollars in thousands):