Much of the increase in the Fed’s assets has come in the form of U.S. Treasury securities and Freddie Mac and Fannie Mae mortgage-backed securities that the Fed purchased over the last five years in its attempts to stimulate the economy.

As of Feb. 1, 2006, when Bernanke took over as chairman, the Fed’s balance sheet indicated it owned  $748,840,000,000 in U.S. Treasury securities. At that time, the balance sheet listed no mortgage-backed securities. As of Jan. 29, 2013, the balance sheet indicated the Fed owned $2,243,176,000,000 in U.S. Treasury securities and $1,532,224,000,000 in mortgage-backed securities.