US markets extend rebound: S&P 500 opens +0.51%

Investors could take a break from worries over the China economy as markets there were shut for two days for a holiday to mark World War II Victory Day. The broader S&P 500 gained 14.35 (0.74 percent) at 1,963.21, while the Nasdaq Composite added 20.77 (0.44 percent) at 4,770.75. Shares rallied solidly Wednesday, with a surge in buying in the final half-hour, despite growing evidence that China's slowdown will spill over to other emerging economies and global growth more broadly.