For the three and nine months ended September 30, 2023, gross investment income totaled $59.6 million and $169.5 million, respectively. For the three and nine months ended September 30, 2022, gross investment income totaled $47.6 million and $123.4 million, respectively. The increase in gross investment income for the year over year three month periods was primarily due to net growth of the income producing portfolio as well as an increase in index rates.
Net expenses totaled $36.3 million and $101.3 million, respectively, for the three and nine months ended September 30, 2023, of which $13.8 million and $40.6 million, respectively, were base management fees and performance-based incentive fees and $19.9 million and $53.0 million, respectively, were interest and other credit facility expenses. Over the same periods, $0.2 million and $0.4 million of performance-based incentive fees were waived. Administrative services and other general and administrative expenses totaled $2.7 million and $8.2 million, respectively, for the three and nine months ended September 30, 2023. Net expenses totaled $27.5 million and $69.5 million, respectively, for the three and nine months ended September 30, 2022, of which $12.9 million and $31.7 million, respectively, were base management fees and gross performance-based incentive fees and $12.8 million and $31.5 million, respectively, were interest and other credit facility expenses. Over the same periods, $0.2 million and $1.6 million, respectively, of performance-based incentive fees were waived. Administrative services and other general and administrative expenses totaled $2.1 million and $7.9 million, respectively, for the three and nine months ended September 30, 2022. Expenses generally consist of management and performance-based incentive fees, interest and other credit facility expenses, administrative services fees, insurance expenses, legal fees, directors’ fees, transfer agency fees, printing and proxy expenses, audit and tax services expenses, and other general and administrative expenses. Interest and other credit facility expenses generally consist of interest, unused fees, agency fees and loan origination fees, if any, among others. The increase in expenses for the three and nine months ended September 30, 2023 versus the three and nine months ended September 30, 2022 was primarily due to higher management fees, incentive fees and interest expense on a larger portfolio. Additionally, there was an increase in index rates on borrowings.
The Company’s net investment income totaled $23.4 million and $68.2 million, or $0.43 and $1.25, per average share, respectively, for the three and nine months ended September 30, 2023. The Company’s net investment income totaled $20.1 million and $53.8 million, or $0.37 and $1.06, per average share, respectively, for the three and nine months ended September 30, 2022.
The Company had investment sales and prepayments totaling approximately $206 million and $473 million, respectively, for the three and nine months ended September 30, 2023. Net realized losses over the same periods were $31.0 million and $29.8 million, respectively. The Company had investment sales and prepayments totaling approximately $81 million and $261 million, respectively, for the three and nine months ended September 30, 2022. Net realized losses over the same periods were $37.3 million and $37.4 million, respectively. Net realized losses for the three and nine months ended September 30, 2023 were primarily related to our investment in American Teleconferencing Services, Ltd. Net realized losses for the three and nine months ended September 30, 2022 were primarily related to our investment in PhyMed Management, LLC.
Net Change in Unrealized Gain (Loss)
For the three and nine months ended September 30, 2023, net change in unrealized gain on the Company’s assets totaled $34.5 million and $14.4 million, respectively. Net unrealized gain for the three months ended September 30, 2023 is primarily due to the reversal of previously recognized unrealized depreciation on our investment in American Teleconferencing Services, Ltd. as well as appreciation in the value of our investments in Alimera Sciences, Inc. and SLR Credit Solutions, among others, partially offset by depreciation in the value of our investments in KBH Topco, LLC, among others. Net unrealized gain for the nine months ended September 30, 2023 is primarily due to the reversal of previously recognized unrealized depreciation on our investment in American Teleconferencing Services, Ltd. as well as appreciation in the value of our investments in Alimera Sciences, Inc., among others, partially offset by depreciation in the value of our investments in Oldco AI, LLC (f/k/a AmeriMark), SLR Credit Solutions and KBT Topco, LLC, among others. For the three and nine months ended September 30, 2022, net change in unrealized gain (loss) on the Company’s assets and liabilities totaled $30.8 million and ($17.1) million, respectively. Net unrealized gain for the three months ended September 30, 2022 is primarily due to the reversal of previously recognized unrealized depreciation on our investment in PhyMed Management LLC, as well as appreciation in the value of our investments in SLR Business Credit, Alimera Sciences, Inc. and Kingsbridge Holdings, LLC, among others, partially offset by depreciation in the value of our investments in SLR Equipment Finance, PPT Management Holdings, LLC, KBH Topco, LLC, SLR Healthcare ABL and SLR Credit Solutions, among others. Net unrealized loss for the nine months ended September 30, 2022 is primarily due to depreciation in the value of our investments in RD Holdco, Inc., American Teleconferencing Services, Ltd., SLR Credit Solutions and SLR Equipment Finance, among others, partially offset by the reversal of previously recognized unrealized depreciation on our investment in PhyMed Management LLC as well as appreciation on the value of our investments in SLR Business Credit and Alimera Sciences, Inc. in addition to unrealized appreciation on assets acquired in the Mergers due to the accounting treatment of the purchase discount.
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