NOTE 3 —INVESTMENTS IN MARKETABLE DEBT SECURITIES

Investments in marketable debt securities, are accounted for as available-for-sale investments consisting of the following (in thousands):

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The Company’s investments in debt securities are subject to interest rate risk and credit risk that results in differences between amortized cost basis and the fair value of investments. To minimize the exposure due to an adverse shift in interest rates, the Company generally invests in securities with expected maturities of two years or less and maintains a weighted average maturity of one year or less. As of September 30, 2023, investments in marketable debt securities with an aggregate fair value of $90.7 million are scheduled to mature during the 12-month period ending September 30, 2024. Substantially all of the remaining investments, with an aggregate fair value of $8.1 million, are scheduled to mature during the 12-month period ending September 30, 2025.

During the three months ended September 30, 2023, marketable debt securities for $18.6 million matured and approximately $16.0 million of the proceeds were reinvested in additional marketable debt securities.  The Company did not sell any marketable debt securities prior to the scheduled maturity dates for the three months ended September 30, 2023.

Accrued interest receivable on all marketable debt securities amounted to $0.4 million and $0.3 million as of September 30, 2023 and June 30, 2023, respectively. Accrued interest receivable is included in other current assets in the accompanying condensed consolidated balance sheets.

For the three months ended September 30, 2023, the Company did not recognize any allowance for credit losses related to investments in marketable debt securities. The following table summarizes the cumulative unrealized gains and losses that result in differences between the amortized cost basis and fair value of the Company’s marketable debt securities held as of September 30, 2023 (in thousands):

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