Traders signal offers Monday in the Standard & Poor's 500 stock index options pit at the Chicago Board Options Exchange. Major market indexes tumbled around the world amid worries about China's slowing economy. Scott Olson/Getty Images hide caption

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A poor economy and nine years of recession have caused many to leave Puerto Rico. Margalit Francus/Flickr hide caption

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PREPA's Central Palo Seco power station in San Juan, Puerto Rico. The utility's bondholders want to raise rates. That's a challenge when the median income is about half that of Mississippi, yet the U.S. territory's energy costs are among the highest in the nation. Alvin Baez-Hernandez/Reuters/Landov hide caption

itoggle caption Alvin Baez-Hernandez/Reuters/Landov

Protesters gather April 30 outside Puerto Rico's Capitol building in San Juan to oppose Gov. Alejandro Garcia Padilla's budget proposal. The plan would raise taxes to help cover the state's massive debt. Ricardo Arduengo/AP hide caption

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The Citigroup Center is viewed in midtown Manhattan. Critics say the U.S. settlement with the banking giant will do nothing for those hurt most by the foreclosure crisis: people who lost their homes. Timothy A. Clary/AFP/Getty Images hide caption

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Citigroup has agreed to pay $7 billion to settle a federal investigation into subprime mortgages it sold in the run-up to the financial meltdown of 2008. Kiichiro Sato/AP hide caption

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President Obama with Paul Volcker at the White House in 2009. Volcker, who headed the President's Economic Recovery Advisory Board, lent his name to a new rule aimed at curbing risk-taking on Wall Street. Brendan Smialowski/Getty Images hide caption

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