U.S. Stocks Open Lower, On Track To Post Steep Weekly Losses

U.S. stocks extended this week's losses with a renewed selloff on Friday. The main indexes are on track to post the steepest weekly declines since last May 2012. The S&P 500 opened 19 points, or 0.9%, lower at 2,016. The benchmark index fell below a 200-day moving average on Thursday, a key technical level. The Dow Jones Industrial Average dropped 165 points, or 1%, to 16,824. The Nasdaq Composite began the day down 70 points, or 1.4%, to 4,707.