Nyse

20120530-191933-pic-840840549.jpg

Specialist Allison Gamba works at her post on the floor of the New York Stock Exchange on Wednesday. U.S. stocks opened sharply lower on concerns about the stability of Europe's financial system. (Associated Press)

Wall Street_Live.jpg

Specialist Michael Pistillo (center) works May 30, 2012, at his post on the floor of the New York Stock Exchange. (Associated Press)

Wall Street_Live.jpg

Trader Edward Radziewicz (left) works May 29, 2012, on the floor of the New York Stock Exchange. (Associated Press)

Wall Street_Live.jpg

**FILE** Trader John Bishop works May 7, 2012, on the floor of the New York Stock Exchange. (Associated Press)

20120513-192526-pic-146279734.jpg

Specialist Peter Giacchi (center) calls out prices as he works at the post that handles JP Morgan Chase stock on the floor of the New York Stock Exchange, on Friday. The bank's trading loss of $2 billion will cost three high-ranking executives their jobs. (Associated Press)

20120507-200801-pic-410567631.jpg

Traders Michael Zicchinolfi (left) and Vincent Quinones keep an eye on prices Monday on the floor of the New York Stock Exchange. U.S. stocks were under pressure after angry voters in Greece and France rejected painful budget cuts demanded by international lenders. But investors did not panic about the election news. (Associated Press)

Wall Street_Lea.jpg

** FILE ** Specialists Peter Giacchi (left) and John Parisi confer on the floor of the New York Stock Exchange on Wednesday, April 25, 2012. (AP Photo/Richard Drew)

e0fabf4ae0aa020b0e0f6a706700224c.jpg

In an April 23, 2012 photo Robert Arciero, right, works with fellow traders on the floor of the New York Stock Exchange. Wall Street headed for a mixed opening Friday April 27, 2012, with Dow Jones industrial futures slipping marginally while the S&P 500 futures fell 0.1 percent (AP Photo/Richard Drew)