Buckshot the bull is corralled in front of the New York Stock Exchange as part of a promotion, January 8, 2009. Members of the Professional Bull Riders, Inc. rang the opening bell at the stock exchange to promote the PBR's Built Ford Tough Invitational at Madison Square Garden. U.S. stocks extended losses on Thursday after Wal-Mart Stores Inc posted disappointing December sales and cut its fourth-quarter profit outlook, compounding investors' concerns about the worsening recession. REUTERS/Brendan McDermid (UNITED STATES)