On December 22, the Federal Deposit Insurance Corporation (FDIC) stated in its quarterly bank profile report that the number of US banks on its "Problem Bank List" rose to 68 in the third quarter. As of the third quarter of this year, bank book losses reached $364 billion, mainly due to banks' involvement in residential real estate and government bond markets. Unrealized losses represent the difference between what a bank paid for securities and their current market value. In the third quarter, bank book losses decreased by $148.9 billion from $512.9 billion in the second quarter.