The interest expense increase of $42 thousand for the nine months ended June 30, 2022 as compared to the prior year period is related to the TS U.S. division entering into multiple multi-year contracts starting in the second quarter of fiscal year 2021 causing fiscal year 2022 to increase due to a full nine months of interest expense incurred. Payments on these agreements contain both principal and interest expense. See Note 10 in Item 1 to this Quarterly Report on Form 10-Q for details.
Income Taxes
The income tax expense of $28 thousand for the nine months ended June 30, 2022 is primarily driven by minimum state tax expenses, as the Company continues to maintain a full valuation allowance on their operations. The income tax expense of $868 thousand for the nine months ended June 30, 2021 was primarily driven by an increase in the valuation allowance against deferred tax assets in the period, offset by a benefit recorded for the change in tax law, allowing for the immediate deduction of covered expense incurred through the Paycheck Protection Program.
We have in general historically calculated the provision for income taxes during interim reporting periods by applying an estimate of the annual effective tax rate for the full calendar year to ordinary income or loss for the reporting period. However, we used a discrete effective tax rate method to calculate income taxes for the quarter ended June 30, 2022 because we determined that our ordinary income or loss cannot be reliably estimated and small changes in estimated ordinary income would result in significant changes in the estimated annual effective tax rates.
Liquidity and Capital Resources
Our primary source of liquidity is our cash and cash equivalents, which increased by $1.4 million to $21.4 million as of June 30, 2022 from $20.0 million as of September 30, 2021.
Our significant sources of cash for the nine months ended June 30, 2022 included an increase in deferred revenue of $2.9 million, an increase of $2.1 million in net amount received under the line-of-credit agreement, and a decrease in accounts receivable and long-term receivable of $2.1 million.
Our significant uses of cash for the nine months ended June 30, 2022 were primarily related to a decrease in accounts payable and accrued expenses and other long-term liabilities of $2.1 million, an increase in inventory of $1.6 million, repayment of life insurance policy loans of $0.9 million, repayments on debt of $0.7 million, and purchases of property, equipment, and improvements of $0.2 million.
Our cash held by our foreign subsidiary in the United Kingdom totaled approximately $8.9 million as of June 30, 2022 and consisted of 0.4 million Euros, 0.3 million British Pounds, and 8.3 million U.S. Dollars. This cash is included in our total cash and cash equivalents reported within our financial statements.
As of June 30, 2022 and September 30, 2021, the Company maintained a line of credit with a capacity of up to $15.0 million for inventory accessible to both the HPP and TS segments. This line of credit also includes availability of a limited cash withdrawal of up to $1.0 million. An amount of $12.0 million and $14.1 million were available as of June 30, 2022 and September 30, 2021, respectively. As of June 30, 2022 and September 30, 2021 there were no cash withdrawals outstanding. For a further discussion of the Company’s line of credit, including its financial covenants, see Item 1, Note 10 “Notes Payable and Line of Credit.”
If cash generated from operations is insufficient to satisfy working capital requirements, we may need to access funds through bank loans or other means. If we are unable to secure additional financing, we may not be able to complete development or enhancement of products, take advantage of future opportunities, respond to competition, retain key employees, or continue to effectively operate our business.
Based on our current plans and business conditions, management believes that the Company’s available cash and cash equivalents, the cash generated from operations, and availability on our line of credit will be sufficient to provide for the Company’s working capital and capital expenditure requirements for at least 12 months from the date of this filing.