In his dissent to the majority report of the Financial Crisis Inquiry Commission, American Enterprise Institute fellow Peter J. Wallison stated his belief that the roots of the financial crisis can be traced directly and primarily to affordable housing policies initiated by HUD in the 1990s and to massive risky loan purchases by government-sponsored entities Fannie Mae and Freddie Mac. Later, based upon information in the SEC's December 2011 securities fraud case against 6 ex-executives of Fannie and Freddie, Peter Wallison and Edward Pinto estimated that, in 2008, Fannie and Freddie held 13 million substandard loans totaling over $2 trillion.

Which government-sponsored entities had massive risky loan purchases?