Wall Street opens lower on Fed stimulus uncertainty

Wall Street opened lower Wednesday as uncertainty over how soon the Federal Reserve will begin to scale back its stimulus efforts curbed investors' appetite for risky assets.

The Dow Jones industrial average fell 66.85 points or 0.42 percent, to 15,683.82, the S&P 500 lost 5.86 points or 0.33 percent, to 1,761.83 and the Nasdaq Composite dropped 20.265 points or 0.52 percent, to 3,899.656.