The US federal gas tax has gone down since 1993 in any way you measure it except nominal dollars per gallon (since it has been fixed in nominal dollars per gall

The US federal gas tax has gone down since 1993 in any way you measure it except nominal dollars per gallon (since it has been fixed in nominal dollars per gallon since 1993). It's low enough now to neither be an effective excise tax (it's lower than sales tax in some places), nor fund the federal spend on highways. Nominal dollars per mile: gone down by about 10% on average since cars have gotten more efficient since 1993 Real cost per gallon: gone down by more than half, since we've had ~116% inflation since 1993 Real cost per mile: just multiply the two together and it's about 60% lower than it was in 1993. Percentage of spend on gasoline: Gas was $1.11 per gallon in 1993, and it's about triple that today.