M-RCBG Faculty Working Paper No. 2010-02
Fuel Tax Incidence and Supply Conditions
Justin Marion and Erich Muehlegger
In this paper, we provide new evidence regarding the pass-through of diesel and gasoline taxes to prices, and how the estimated pass-through depends on a variety of supply conditions including a measure of state residual supply elasticity, and refinery and inventory constraints. In addition, we estimate the response of tax incidence to gasoline content regulations, which complicate the supply chain by increasing product heterogeneity. We find that state gasoline and diesel taxes are on average fully passed on to consumers. We also find that the pass-through of diesel taxes is greater in settings where untaxed uses of diesel are more important, which corresponds to times when residual supply is more elastic. We find that only half of the state diesel tax is passed on to consumers when U.S. refinery capacity utilization is above 95 percent. Gasoline taxes, on the other hand, are fully passed through regardless of season or capacity utilization, indicating that a gas tax holiday would provide price relief to consumers. We find that regional gasoline content regulations affect pass-through – we estimate tax pass-through is 22 percentage points lower in a state using two blends of gasoline than a state using one blend of gasoline.