From sfgate.com......

When Citigroup warned in early November that it was likely to write down its portfolio by $8 billion to $11 billion in the fourth quarter because of exposure to bad loans, investors recoiled at the size of the losses. Some now say those early estimates appear drastically understated.

Citigroup Inc. could write off as much as $18.7 billion in the fourth quarter, wrote Goldman analysts William F. Tanona, Betsy Miller and Neil C. Sanyal in a note to investors late Wednesday. If it does, they say, the bank may be forced to lower its dividend by 40 percent.

Citi has about $55 billion in exposure to subprime mortgages, about $43 billion of which are collateralized debt obligations, or CDOs, that have mortgages underlying them.