By Steve Goldstein

WASHINGTON (MarketWatch) — The Federal Reserve released earnings for 2010, with the central bank’s profit growing to $81.7 billion, a record high, from $53.4 billion, mostly due to growing interest earnings on federal agency and government-sponsored enterprise mortgage-backed securities. The Fed’s balance sheet — which also can be monitored monthly — ballooned to $2.43 trillion, up $193 billion from 2009, as holdings of U.S. Treasury and mortgage-backed securities rose. The Fed returned $79 billion to the U.S. Treasury in 2010, up from $47 billion in 2009. (Updates to include that the Fed profits were at a record.)