China crisis: What are US stock circuit breakers?

Investors look at a computer screen in front of an electronic board showing stock information at a brokerage house in Fuyang, Anhui province, China. Photo: Reuters

Nasdaq 100 September futures NQc1 were halted in premarket trading on Monday after falling to 3,992.25, marking a 5pc drop in overnight hours.

According to CME Group, the equity index price limits are designed to coordinate with circuit breaker provisions the New York Stock Exchange has in place.