The relationship between recent gasoline price fluctuations and transit ridership in major US cities

The unprecedented increase in gasoline costs between August 2005 and July 2008 has become a major public issue in the US. Of the contentions and potential solutions surrounding higher gasoline costs, one receiving relatively little attention has been the role of public transit. This research examines that question by analyzing the relationship between gasoline prices and transit ridership from January 2002 to April 2008 in nine major US cities. Regression analysis is used to assess the degree to which variability in rail and bus transit ridership is attributable to gasoline costs and fluctuations in gasoline cost, controlling for service changes, seasonality, and inherent trending. The results indicate that a small but statistically significant amount of ridership fluctuation is due to changes in gasoline prices. The results are discussed in light of the policy and practical implications of higher gasoline prices for mass transit and the potential for long term changes in US travel behavior.