New york: The main stock indices on the US Wall Street Stock Exchange closed lower at the end of today's trading. According to Qatar News Agency, the S and P 500 index ended trading down 16.01 points, or 0.27 percent, to 5,816.91 points. The Nasdaq Composite Index fell 96.37 points, or 0.52 percent, to close at 18,616.38. Meanwhile, the Dow Jones Industrial Average fell 65.14 points, or 0.15 percent, to close at 42,167.91.