Replacing the Gas Tax: Leveraging the Electric Vehicle Transition to Build a Stronger Transportation Funding System in the United States

The federal Highway Trust Fund, which is the foundation for federal transportation funding and funded by the federal excise on gasoline, has been eroded by increasingly fuel efficient vehicles, the increasing adoption of PHEVs and EVs, and the faiure of Congress to adjust the federal as tax to inflation. As a result, throough most of this century, Congress has had to appropriate additional funds to maintain a bare sense of addequancy in the Trust Fund. This report uses a dynamic model to understand the effects of a variety of policies and interventions, and proposes a framnework for replacing the gas tax by offering a short list of feasible alternatives to the gas tax, evaluating each according to metrics geared toward the performance and efficiiency of each.