FACTBOX: U.S. mortgage lenders

NEW YORK (Reuters) - U.S. mortgage lenders are suffering from rising default rates amid weak housing prices and slower sales in the housing market.

Subprime lenders, which serve borrowers with poor credit histories, have been hard hit. Many lenders lowered their underwriting standards too far, and as a result more than two dozen quit or sold their businesses, or went bankrupt.

Shares of major U.S. mortgage lenders have fallen by about 20 percent to upward of 90 percent since early February. The following is recent news involving selected lenders. For more stories, please click on

ACCREDITED HOME LENDERS HOLDING CO.

-- Delayed filing its annual report, saying it may need to write off some goodwill it acquired when it bought rival Aames Investment Corp. last year.

-- Subprime mortgage lender

Headquarters: San Diego

AMERIQUEST MORTGAGE CO.

-- ACC Capital, Ameriquest's parent, obtained working capital from Citigroup Inc. and gave the bank an option to buy its wholesale mortgage origination and servicing units.

-- Subprime mortgage lender

Headquarters: Orange, California

COUNTRYWIDE FINANCIAL CORP.

-- Said nearly one in five borrowers on nonprime loans it services were delinquent in the fourth quarter.

-- Tightened underwriting standards.

-- Largest mortgage lender, fourth-largest subprime lender

Headquarters: Calabasas, California