New york: Major stock indexes on the US Wall Street Exchange closed mixed at the end of today's trading session. According to Qatar News Agency, the S and P 500 index ended the session down by 16.40 points, or 0.26%, closing at 6,394.97 points. The Nasdaq Composite index also declined by 144.76 points, or 0.68%, finishing at 21,170.19 points. Meanwhile, the Dow Jones Industrial Average edged up by 1.48 points, ending the day at 44,923.75 points.