If the taxes that are currently credited to the trust fund remained in place and if funding for highway and transit programs increased annually at the rate of inflation, the shortfalls accumulated in the Highway Trust Fund’s highway and transit accounts from 2024 to 2033 would total $241 billion, according to CBO’s May 2023 baseline budget projections Declining federal highway user tax revenues are forecast to total $37 billion by 2033, while projected spending would be $65 billion that year.