WASHINGTON — Profits at U.S. banks jumped almost 37 percent from October through December, reaching the highest level in six years as banks continued to step up lending.

The figures are fresh evidence of the industry’s sustained recovery four years after the financial crisis.

Banks earned $34.7 billion in the fourth quarter, the highest since the same period in 2006, the Federal Deposit Insurance Corp. reported Tuesday. Sixty percent of banks reported improved earnings from the fourth quarter of 2011, the agency said.

The FDIC, created during the Great Depression to ensure bank deposits, monitorsthe financial condition of U.S banks.

For all of 2012, the agency said bank earnings rose 19 percent to $141.3 billion, the second-highest annual level ever.