If the S&P 500 drops 20%, and triggers a level 3 circuit breaker, trading would stop for the rest of the day. The S&P 500 traded as low as 5,101.75 on Friday, down more than 5%. While this ...

"A cross-market trading halt can be triggered at three circuit breaker thresholds — 7% (Level 1), 13% (Level 2), and 20% (Level 3)," the rule says. "These triggers are set by the markets at ...

A Level 1 circuit breaker stops trade for a minimum of 15 minutes if the S&P 500 falls 7% before 3:25 p.m. Eastern time. -- Once trading resumes, a further decline to 13% before 3:25 p.m. would ...