Traders work on the floor of the New York Stock Exchange (NYSE) in New York, U.S., on Monday, June 13, 2016. U.S. stocks fluctuated, after the S&P 500 Index's steepest loss in three weeks, as optimism spurred by one of the largest technology takeovers ever helped dilute concern over a pair of coming central-bank events that have sowed anxiety. Photographer: Michael Nagle/Bloomberg via Getty Images
