Highway Trust Fund Revenue Shortfalls (2008–Present)
The federal Highway Trust Fund, which finances surface transportation and partly parallels the Airport and Airway Trust Fund structure, began running persistent shortfalls as fuel tax revenue stagnated while construction costs rose. Congress transferred over $275 billion from general revenues to keep the fund solvent rather than raising the gas tax, which has been frozen at 18.4 cents per gallon since 1993.
Each transfer averted a funding cliff, but the structural mismatch between dedicated revenue and spending needs persisted.
The pattern of temporary fixes and periodic infusions set the political template for infrastructure funding: large supplemental packages like the IIJA rather than sustainable dedicated revenue reforms.
The airport funding gap follows the same structural pattern: a dedicated trust fund (the Airport and Airway Trust Fund) and a user fee (the PFC) that have not kept pace with costs, filled by periodic congressional supplements that create boom-and-bust cycles.
