Around 3:40 p.m. on a recent trading day, a dozen or so brokers at the New York Stock Exchange hustled back to their posts after bathroom breaks and a last coffee. They strapped on headphones to prepare for the closing minutes of the U.S. stock market—the pinnacle moment for investors world-wide.
As the clock neared 4 p.m., a buzz grew on the trading floor of mutual-fund giant Vanguard Group 100 miles away in Malvern, Pa., while
head of U.S. equity trading, and his team prepared billions of dollars in trades.
In downtown Milwaukee,
a trader for R.W. Baird & Co., joined the late-afternoon countdown, poring through data from the exchanges while entering stock orders for large mutual- and pension-fund clients.
Percentage of daily volume in S&P 500 stocks by half-hour interval