Comparison of the nine months ended March 31, 2021 and March 31, 2020
Investment income
Investment income, attributable primarily to interest and fees on our debt investments, for the nine months ended March 31, 2021 decreased to $20.1 million from $26.8 million for the nine months ended March 31, 2020, primarily due to a decrease in assets under management and the first and second lien investments in Premiere Global Services, Inc. being placed on non-accrual status.
Expenses
Total expenses for the nine months ended March 31, 2021 decreased to $12.5 million, compared to $16.1 million for the nine months ended March 31, 2020, primarily due to a decrease in interest expenses related to decreased borrowings under the Revolving Financing, lower base management fees and no income-based fees during the three months ended March 31, 2021.
Net investment income
Net investment income decreased to $7.6 million for the nine months ended March 31, 2021 from $10.7 million for the nine months ended March 31, 2020, primarily due to a decrease in investment income offset by a decrease in expenses compared to the prior period offset by an increase in investment income during the same period.
Net realized gain or loss
Net realized losses on investments totaled $3.6 million for the nine months ended March 31, 2021, primarily due to the restructure of Bioplan USA, Inc. and the termination of PR Wireless, Inc., $0.01 strike (Warrants) offset by the sale of BW Gas & Convenience. Net realized losses on investments totaled $7.6 million for the nine months ended March 31, 2020, primarily due to the restructure of Fusion Connect, Inc. and 4L Technologies, Inc.
Net change in unrealized (depreciation) appreciation on investments
We recorded a net change in unrealized appreciation of $5.6 million for the nine months ended March 31, 2021, primarily due to the increase in the value of Bioplan USA, Inc., CB URS Holdings Corporation, Pixelle Specialty Solutions LLC, and Techniplas LLC Common Stock offset by the decrease in value of 1888 Industrial Services, LLC, Premiere Global Services, Inc, and ZeroChaos Parent, LLC.
During the nine months ended March 31, 2020, we recorded a net change in unrealized depreciation of $25.3 million, primarily due to the decrease in the value of 1888 Industrial Services, 4L Technologies Inc, Bioplan USA, Inc., DSG Entertainment Services, Inc., Fusion Connect Inc., GEE Group Inc., Premiere Global Services, Inc. and Techniplas LLC. The resulting changes in net unrealized depreciation on investments were largely due to widening credit spreads as market participants expected a higher yield on similar investments given the significant market volatility generated by the COVID-19 pandemic.
Liquidity and capital resources
Cash flows
For the nine months ended March 31, 2021, our unrestricted cash balance increased by $65 million. During that period, cash increased by $38.6 million from operating activities, primarily due to sales of investments of $71.1 million in portfolio companies and offset by payments for the purchase of investments in portfolio companies of $45.7 million. During the same period, cash from financing activities increased by $27.6 million, consisting primarily of proceeds of $65 million from the 2026 Notes, repayments of $30 million from borrowings under the Revolving Financing and distributions of $7.5 million to our stockholders.
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