The Dow Jones industrial average had one of the most turbulent trading days in its history and suffered its biggest intraday loss. Worries about Europe's debt crisis started the market lower, and the selling accelerated in the early afternoon. Computer problems were being investigated for possibly worsening the sell-off.
Here are some facts and figures about the Dow's big day and where it stands, provided by Dow Jones & Co.:
The Dow Jones industrial average closed down 347.80, or 3.2 percent, at 10,520.32, its biggest point loss since February 2009.
It had been down as much as 998.5 points, or 9.2 percent.
It was the biggest intraday drop in its history.
The Dow is now down 631.51 points, or 5.7 percent, the past three days. That's the biggest three-day point drop since November 2008 and the biggest three-day percentage drop since March 2009.
The index had a swing of 1,010.14 points between its highest and lowest levels of the day.
The Dow is 25.7 percent below its record close of 14,164.53 on October 9, 2007.
It is up 60.7 percent from its 12-year low close of 6,547.05 on March 9, 2009.
Despite its big losses this week, the Dow is still up 0.9 percent so far this year.
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