During the quarter ended June 30, 2012, we closed $220.6 million of investments in 10 new and six existing portfolio companies, and funded $203.5 million across new and existing portfolio companies. This compares to closing $120.1 million of new investments and funding $119.2 million during the quarter ended June 30, 2011. During the quarter ended June 30, 2012, we also received $55.1 million in connection with the exits of three of our portfolio companies, all of which were exited at or above par.
At June 30, 2012, our portfolio consisted of investments in 76 companies, 67 of which were completed in connection with investments by private equity sponsors and nine of which were in private equity funds. At fair value, 97.5% of our portfolio consisted of debt investments (69.4% were first lien loans, 11.1% were second lien loans and 17.0% were subordinated loans). Our average portfolio company investment size at fair value (excluding equity-only investments) was $19.3 million at June 30, 2012, versus $20.4 million at September 30, 2011.
"Our deal activity continued to grow last quarter, with the number of transactions increasing over second quarter levels, which strengthens our platform as we head towards the end of our 2012 fiscal year," stated Fifth Street's President, Bernard D. Berman.
Our weighted average yield on debt investments at June 30, 2012 was 12.13%, and included a cash component of 10.92%.At June 30, 2012 and September 30, 2011, $795.3 million and $739.8 million, respectively, of our portfolio of debt investments at fair value were at floating rates, which represented 68.1% and 67.3%, respectively, of our total portfolio of debt investments at fair value. Results of Operations Total investment income for the quarters ended June 30, 2012 and June 30, 2011 was $41.0 million and $32.4 million, respectively. For the quarter ended June 30, 2012, this amount primarily consisted of $32.6 million of interest income from portfolio investments (which included $3.9 million of PIK interest). For the quarter ended June 30, 2011, total investment income primarily consisted of $29.0 million of interest income from portfolio investments (which included $3.6 million of PIK interest).