Merrill Lynch and Co. reported Tuesday a $15.84 billion loss -- or $9.95 per share -- in the fourth quarter of 2008, according to a report filed with the U.S. Securities and Exchange CommissionBank of America Corp. (BAC), which acquired Merrill Lynch in early September, estimated in January that Merrill would lose $15.31 billion in the fourth quarter --  $533 million less than the actual loss. Merrill Lynch lost a total of $27.61 billion, or a whopping $24.87 per share,  over the course of 2008, chiefly due to large writedowns and investment losses on CDOs and other risky securities. The annual report said the recently acquired bank experienced material weaknesses related to a failure to properly test measurements used to value intercompany swaps, and a failure to properly account for some hedging positions, including a "single material hedge relationship" which began in the fourth quarter, according to a Reuter's report. However, Merrill said it has corrected the problems and will look to eliminate those weaknesses this quarter. Write to Kelly Curran at Disclosure: The author held no relevant investment positions when this story was published. Indirect holdings may exist via mutual fund investments. HW reporters and writers follow a strict disclosure policy, the first in the mortgage trade.