A Pakistani investor sits at a trading floor of Karachi Stock Exchange in Karachi, Pakistan on Friday, Aug 5, 2011. Asian stock markets tumbled Friday amid fears the U.S. may be heading back into ... more 
A Pakistani investor sits at a trading floor of Karachi Stock Exchange in Karachi, Pakistan on Friday, Aug 5, 2011. Asian stock markets tumbled Friday amid fears the U.S. may be heading back into recession and Europe's debt crisis is worsening. (AP Photo/Fareed Khan) less 
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Associated Press | Photo By Fareed Khan
Fri, Aug 5, 2011 8:44 AM EDT