New York Stock Exchange circuit breakers triggered four times during the March 2020 market crash.
The automatic halts occurred on 9, 12, 16 and 18 March 2020, when the S&P 500 fell 7% from its previous close shortly after trading began. Each halt lasted 15 minutes under the applicable Level 1 rules. The mechanism was intended to give investors time to absorb information and reduce panic-driven selling.
The crash was linked to the economic shock from the COVID-19 pandemic, uncertainty about business shutdowns and an oil-price dispute between Saudi Arabia and Russia. The Dow Jones Industrial Average entered a bear market in March after reaching a record high in February. The circuit breakers did not prevent the overall decline, but they temporarily interrupted its fastest waves and demonstrated how post-1987 market safeguards operate.