Update:
In March 2011, The United States Congressional Budget Office issued a report comparing the relative merits of fuel taxes, vehicle excise taxes, vehicle tire excise taxes, and a hypothetical vehicle miles traveled tax. [7] It emphasized the disproportionate road wear of cargo trucks versus the current tax rate paid, but noted that costs assessed to this sector would be passed along to the consumer. Also noteworthy was a chart indicating that the excise tax on tires could provide motivation to vehicle owners to reduce many external costs of vehicle travel and road maintenance, but it is currently set far too low to have much effect. The report noted that a GPS-based tax would have a unique trait in allowing taxes to be increased in high congestion zones where tolls are not practical, with the caveat that advances in toll collection technology would mitigate this advantage. The report also emphasized that both tire taxes and vehicle mile traveled taxes would have to be rated based on weight-per-axle to properly distribute wear-related costs of highway use.