Video PlayerClose
Traders work at the New York Stock Exchange in New York, the United States, on March 18, 2020. The S&P 500 tumbled 7 percent at around 1 p.m. Eastern Time, triggering a key circuit breaker that halted trading for 15 minutes. It was the second time this week that the circuit breaker has been tipped. (Photo by Michael Nagle/Xinhua)