Wall Street traders are enduring fresh equity-market fireworks Friday after another week of global turbulence.
Stock transactions spiked at the open as the expiry of stock and index options collided with that of index futures in a quarterly event known as triple witching. In the first 15 minutes of trading as the benchmark slipped 0.2%, volume on S&P 500 Index was more than double the average for that time of day over the past 30 sessions.
