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"In 1995, the GSEs like Fannie Mae began receiving government tax incentives for purchasing mortgage backed securities which included loans to low income borrowers. Thus began the involvement of the Fannie Mae and Freddie Mac with the subprime market.[117] In 1996, HUD set a goal for Fannie Mae and Freddie Mac that at least 42% of the mortgages they purchase be issued to borrowers whose household income was below the median in their area. This target was increased to 50% in 2000 and 52% in 2005.[118] From 2002 to 2006, as the U.S. subprime market grew 292% over previous years, Fannie Mae and Freddie Mac combined purchases of subprime securities rose from $38 billion to around $175 billion per year before dropping to $90 billion per year, which included $350 billion of Alt-A securities. Fannie Mae had stopped buying Alt-A products in the early 1990s because of the high risk of default. By 2008, the Fannie Mae and Freddie Mac owned, either directly or through mortgage pools they sponsored, $5.1 trillion in residential mortgages, about half the total U.S. mortgage market.[119] The GSE have always been highly leveraged, their net worth as of 30 June 2008 being a mere US$114 billion.[120] When concerns arose in September 2008 regarding the ability of the GSE to make good on their guarantees, the Federal government was forced to place the companies into a conservatorship, effectively nationalizing them at the taxpayers' expense.[121][122]
The Financial Crisis Inquiry Commission reported in 2011 that Fannie & Freddie "contributed to the crisis, but were not a primary cause." GSE mortgage securities essentially maintained their value throughout the crisis and did not contribute to the significant financial firm losses that were central to the financial crisis. The GSEs participated in the expansion of subprime and other risky mortgages, but they followed rather than led Wall Street and other lenders into subprime lending.[92]"