New york: Major Wall Street indices closed mixed at the end of trading today. According to Qatar News Agency, the S and P 500 index fell 19.33 points, or 0.37 percent, to close at 6,339.31. The Nasdaq Composite index rose 8.40 points, or 0.04 percent, to close at 21,138.08. The Dow Jones Industrial Average also fell 320.83 points, or 0.72 percent, to close at 44,140.45.