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U.S. stocks opened lower on Tuesday amid investor concerns over the outcome of Greece's negotiations with creditors and ahead of data that could provide clues on the timing of a U.S. rate hike.
The Dow Jones industrial average fell 42.11 points, or 0.23 percent, to 17,998.26, the S&P 500 lost 5.43 points, or 0.26 percent, to 2,106.3 and the Nasdaq Composite dropped 16.22 points, or 0.32 percent, to 5,066.71.
