FILE - In this Thursday, Oct. 18, 2012, file photo, traders work on the floor of the New York Stock Exchange. World stock markets fell Friday as disappointing U.S. corporate earnings pr

 

              FILE - In this Thursday, Oct. 18, 2012, file photo, traders work on the floor of the New York Stock Exchange. World stock markets fell Friday as disappointing U.S. corporate earnings pr
FILE - In this Thursday, Oct. 18, 2012, file photo, traders work on the floor of the New York Stock Exchange. World stock markets fell Friday as disappointing U.S. corporate earnings provided a reason to book profits on recent gains while investors waited for a progress report from European leaders concluding a summit on the region's debt crisis. Wall Street also looks set to retreat. (AP Photo/Richard Drew, File)