For most of its history, BART's ridership has reflected the U.S. economy, growing modestly during periods of economic expansion and dropping slightly during recessions. A major exception occurred in 1989 in the aftermath of the Loma Prieta earthquake, which severely damaged the San Francisco–Oakland Bay Bridge, causing its closure for a month. BART became the only direct route between the East Bay and San Francisco, resulting in a nearly 17% ridership jump for the 1990 fiscal year. Ridership would not drop back to previous levels after the repair of the bridge until the COVID-19 pandemic began to affect the Bay Area in March 2020.
