US Oregon want to tax motorists for miles driven, not petrol burned.

The state invented the petrol tax in 1919., but officials now want to replace it with a vehicle-miles-travelled (VMT) fee. Under it, drivers would be charged for the distance they consume. GPS-equipped gizmos would track journeys, ensuring that motorists were not charged for driving on private roads or out of state. Those who preferred to keep their whereabouts secret could opt to be charged on odometer readings, or simply to pay a flat fee. A bill that would have applied a VMT fee to all new vehicles doing 55 miles per gallon (mpg) and above died in the last legislative session; instead, 5000 volunteers will join a new VMT scheme in July 2015. They will be charged at 1.5 cents per mile rather than paying the state petrol tax (30 cents per gallon). (The Economist October 19th-25th 2013 P.32)