Aetna announced one of its largest pay hikes recently. CEO Mark Bertolini says he believes it largely could pay for itself by making workers more productive. Courtesy of Aetna hide caption

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Japan's Prime Minister Shinzo Abe speaks during a joint press conference at the White House with President Obama on Tuesday. Abe is urging U.S. lawmakers to approve a trans-Pacific trade deal. Mandel Ngan/AFP/Getty Images hide caption

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Jason Furman, chairman of the White House Council of Economic Advisers, said consumers generally haven't been using the savings from lower gasoline prices to spend on other things. Justin Sullivan/Getty Images hide caption

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President Obama and Japanese Prime Minister Shinzo Abe approach the podiums for a joint press conference Tuesday at the Rose Garden of the White House in Washington. President Obama is hoping to finalize a new trade agreement with Japan and other Asian nations soon. Alex Wong/Getty Images hide caption

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AFL-CIO President Richard Trumka: "Candidates can't hedge their bets any longer, and expect workers to rush to the polls in excitement." Alex Wong/Getty Images hide caption

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People line up to visit St. Peter's Basilica at the Vatican. Although flights to Europe remain expensive, the falling euro is still leading to a surge in American tourists visiting Europe. Andrew Medichini/AP hide caption

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Our modern relationship to property — namely that it's burdensome to own, and therefore less valuable — has allowed the sharing economy to expand. Gustav Dejert/Ikon Images/Corbis hide caption

itoggle caption Gustav Dejert/Ikon Images/Corbis

A reporter stands outside the front door of a house registered to a trading company operated by Navinder Singh Sarao in Hounslow, west of London. on April 22, 2015. Sarao was arrested in connection with the Wall Street flash crash of 2010. Adrian Dennis/AFP/Getty Images hide caption

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