Abstract

Since 2000, vehicle access has increased substantially in California. Between 2000 and 2018, the state added approximately 5.6 million automobiles, roughly one vehicle for every new resident. During the same time period, the share of households in California that do not own a car declined, dropping from 9.5% to just over 7%. Because automobile ownership is an extremely strong determinant of travel behavior, the increase in vehicle availability has important implications for transit use. Individuals living in households with at least one vehicle take the vast majority of their trips by car and have a relatively low likelihood of using transit. Those living in households without cars, by contrast, are a core constituency of transit systems. While less than 7% of households in California do not own a vehicle, these households take approximately 37% of all transit trips in the state.Even prior to the COVID-19 pandemic, transit ridership in California had fallen. From 2014 to 2018, California lost more than 165 million annual boardings, a drop of more than 11%. The close relationship between car access and transit use thus raises a crucial question: has the growth in automobile ownership in California over the past several years depressed the state’s transit ridership?