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MAIN ST CAPITAL CORPORATION ● ● MAIN STREET ANNOUNCES FIRST QUARTER 2021 RESULTS First Quarter 2021 Net Investment Income of $ 0.58 Per Share First Quarter 2021 Distributable Net Investment Income of $ 0.62 Per Share Net Asset Value of $ 22.65 Per Share HOUSTON , May 6 , 2021 – Main Street Capital Corporation ( NYSE : MAIN ) ( " Main Street " ) is pleased to announce its financial results for the first quarter of 2021 . First Quarter 2021 Highlights ● ● ● ● NEWS RELEASE ● Contacts : Main Street Capital Corporation Dwayne L. Hyzak , CEO , dhyzak@mainstcapital.com Brent D. Smith , CFO , bsmith@mainstcapital.com 713-350-6000 Dennard Lascar Investor Relations Ken Dennard / ken@dennardlascar.com Zach Vaughan / zvaughan@dennardlascar.com 713-529-6600 Net investment income of $ 39.8 million ( or $ 0.58 per share ) Distributable net investment income ( ¹ ) of $ 42.1 million ( or $ 0.62 per share ) Total investment income of $ 62.8 million Industry leading ratio of total non - interest operating expenses as a percentage of quarterly average total assets ( " Operating Expenses to Assets Ratio " ) of 1.3 % on an annualized basis for the quarter and 1.4 % for the trailing twelve month ( " TTM " ) period ended March 31 , 2021 Net increase in net assets resulting from operations of $ 57.3 million ( or $ 0.84 per share ) Net asset value of $ 22.65 per share at March 31 , 2021 , representing an increase of $ 0.30 per share , or 1.3 % , compared to $ 22.35 per share at December 31 , 2020 Declared monthly dividends totaling $ 0.615 per share for the second quarter of 2021 , or $ 0.205 per share for each of April , May and June 2021 , consistent with the monthly dividends paid for the second quarter of 2020 and the first quarter of 2021 Completed $ 59.2 million in total lower middle market ( " LMM " ) portfolio investments , including investments totaling $ 53.5 million in two new LMM portfolio companies , which after aggregate repayments of debt principal and return of invested equity capital from several LMM portfolio investments resulted in a net increase of $ 24.5 million in total LMM portfolio investments Completed $ 39.8 million in total private loan portfolio investments , which after aggregate repayments of debt principal and exits of equity investments from several private loan portfolio investments resulted in a net decrease of $ 4.5 million in total private loan portfolio investments Net decrease of $ 35.1 million in middle market portfolio investments Further diversified capital structure and enhanced liquidity by issuing $ 300.0 million of investment grade notes in January 2021 that bear interest at a rate of 3.00 % per year ( the " 3.00 % Notes " ) In commenting on Main Street's results , Dwayne L. Hyzak , Main Street's Chief Executive Officer , stated , " We are pleased with our first quarter results , which we believe illustrate our portfolio companies continued recovery from the impacts of the COVID - 19 pandemic . These first quarter results include the continued improvement in our net asset value per share and the generation of distributable net investment income per share in excess of our monthly dividends paid during the quarter . We also continued our investment origination success in both our lower middle