A circuit breaker was triggered on the New York Stock Exchange on March 9, 2020.
The NYSE halted trading after the S&P 500 fell 7 percent shortly after the opening bell. This was the first activation of the U.S. market’s Level 1 circuit breaker since the mechanism was revised after the 2013 changes. The pause was designed to give investors time to process information and reduce disorderly selling.
The March 9 plunge occurred during the 2020 stock-market crash, when markets reacted to the spread of COVID-19, economic shutdowns, travel restrictions, and a sharp oil-price dispute between Saudi Arabia and Russia. Additional circuit breakers were triggered later in March as the crisis intensified.
A circuit breaker is not a rescue of falling prices and does not guarantee that a market will recover. It is a temporary trading halt based on a specified percentage move. This mechanism differs from a margin call, which requires an investor to provide more collateral or sell assets after losses.