Wall Street flat at open after eight-day run

REUTERS - Wall Street opened flat on Tuesday as profit-taking after the S&P 500's eight-day advance and investor caution about monetary policy outweighed Goldman Sachs' doubling of its quarterly profit.

The Dow Jones Industrial Average was up 3.61 points, or 0.02 percent, at 15,487.87. The Standard & Poor's 500 Index gained 0.76 point, or 0.05 percent, at 1,683.26. The Nasdaq Composite Index added 2.42 points, or 0.07 percent, at 3,609.91. (Reporting by Alison Griswold; Editing by Kenneth Barry)