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General Motors Co. CEO Dan Akerson, right, and other dignitaries celebrate after ringing the opening bell at the New York Stock Exchange in New York, Thursday, Nov. 18, 2010. (AP Photo/Seth Wenig)

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Traders gather near the post where General Motors Co. stock trades at the New York Stock Exchange, Thursday, Nov. 18, 2010. (AP Photo/Seth Wenig)

General Motors Co. CEO Daniel Akerson sits in the driver's seat of a 2011 Chevrolet Camaro in front of the New York Stock Exchange following GM's initial public offering, Thursday, Nov. 18, 2010 in New York. Duncan Niederauer, CEO of NYSE Euronext, is seated at right. (AP Photo/Mark Lennihan)

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General Motors CEO Daniel Akerson sits in the driver's seat of a 2011 Chevrolet Camaro in front of the New York Stock Exchange following GM's initial public offering, Thursday, Nov. 18, 2010, in New York. Duncan Niederauer, CEO of NYSE Euronext, is seated at right. (AP Photo/Mark Lennihan)

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A banner displaying the name of General Motors covers the New York Stock Exchange in New York, Thursday, Nov. 18, 2010. (AP Photo/Seth Wenig)

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FILE - In this Dec. 10, 2010 file photo, AOL Chairman and CEO Tim Armstrong is seen on the floor of the New York Stock Exchange. Investors are running up the price of Yahoo Inc. shares after a report saying AOL Inc. and a group of private equity firms may bid for the Web company.(AP Photo/Richard Drew, file)

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In this Sept. 30, 2010, photo, traders gather at a post on the floor of the New York Stock Exchange, in New York. U.S. stock futures are rising Tuesday, Oct. 5, 2010, following world markets higher after the central bank of Japan moved to weaken the yen.(AP Photo/Richard Drew)

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Traders and specialists work the trading floor of the New York Stock Exchange after the start of trading, Wednesday, Sept. 1, 2010, in New York. (AP Photo/David Karp)

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March 8, 2010, file photograph of a sign for Wall Street near the New York Stock Exchange. Stock futures are rising sharply Monday, Sept. 13, as investors gain confidence in the banking sector following the passage of new global regulations and China's economy continues its robust growth. (AP Photo/Mark Lennihan, file)

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In this Sept. 1, 2010 ,photo, traders and specialists work the trading floor of the New York Stock Exchange, in New York. (AP Photo/David Karp)

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In this photograph taken on Aug. 19, 2010, traders work on the floor of the New York Stock Exchange, in New York. Stock futures are falling as investors continue a sell-off Friday, Aug. 20, that began a day earlier over worries about the pace of economic recovery. (AP Photo/Henny Ray Abrams)

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ASSOCIATED PRESS WAITING FOR GOOD NEWS: Banc of America specialist Peter Giacchi reacts to the numbers on his computer screen on the floor of the New York Stock Exchange on Thursday.

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BIG DROP: A specialist reacts to the plunge on the floor of the New York Stock Exchange on Wednesday. (AP Photo)

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Trader Peter Tuchman (right) watches the numbers as he works on the floor of the New York Stock Exchange on Tuesday, Aug. 10, 2010. (AP Photo/Richard Drew)

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** FILE ** Nicole "Snooki" Polizzi, a cast member of MTV's "Jersey Shore" reality series, is shown at the New York Stock Exchange on July 27, 2010. (AP Photo/Richard Drew, File)

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Nicole "Snooki" Polizzi, foreground, and cast members of MTV's "Jersey Shore" reality series pose for photos on the trading floor after participating in opening bell ceremonies of the New York Stock Exchange Tuesday, July 27, 2010. (AP Photo/Richard Drew)

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In this July 21, 2010, photo, trader John Bowers uses his handheld device as he works on the floor of the New York Stock Exchange. Stock futures are barely off their highs of the morning after the government says weekly jobless claims jumped more than expected last week. (AP Photo/Richard Drew)

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Trader Christopher Lotito, left, checks prices as he works on the floor of the New York Stock Exchange on Wednesday, June 16, 2010. (AP Photo/Richard Drew)

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** FILE ** The board at the New York Stock Exchange. (Associated Press)

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A television screen at the New York Stock Exchange shows the decision of the Federal Reserve to lower interest rates, Wednesday Oct. 8, 2008. The emergency cut led by the Federal Reserve will at least temporarily provide relief for investors who have been battered this week. (AP Photo/Richard Drew)