S & P 500 futures fell 0.3 percent, Nasdaq futures fell 0.5 percent, and Dow Jones index futures fell 0.2 percent.
Nasdaq 100 futures fell 1.1 percent, while Nvidia fell more than 8 percent after hours. Previously, NVIDIA (NVDA. O) released a revenue forecast that fell short of the most optimistic market expectations, raising concerns that its explosive growth was waning.