Fitch downgraded the U.S sovereign rating. The markets took the decision largely on their stride — but that doesn't make the decision inconsequential. Samuel Corum/AFP via Getty Images hide caption
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Trading on the New York Stock Exchange and elsewhere suffered an incredibly volatile week as the Federal Reserve gears up to raise interest rates. Allie Joseph/AP hide caption
It was a wild week for stocks. Should you worry? Here are 4 things to keep in mind
The Justice Department claims Standard & Poor's knew that billions of dollars of mortgage-backed securities were junk but still gave them positive ratings. Emmanuel Dunand/AFP/Getty Images hide caption
Warren Buffett. Donald Bowers/Getty Images for Fortune hide caption