Passenger Transport has created a timeline that tracks key milestones in the history of the motor-fuels tax, more commonly called the gasoline tax, and the diesel fuel tax, both of which partially fund the Highway Trust Fund (HTF) and its Mass ­Transit Account (MTA). The timeline does not track other revenue sources for public ­transportation.

The gas tax has remained at 18.4 cents per gallon of motor fuel since 1993, with the MTA share at 2.86 cents per gallon. The diesel fuel tax—also unchanged from 1993—is 24.4 cents per gallon, with the MTA share also at 2.86 cents. There were no significant changes to either tax from 1959 to 1983. The legislation governing each tax is the same.