Direct subsidy to cars - for roads only - calculated at $1,100 per household.

City Observatory: "The report documents that the amount that road users pay through gas taxes now accounts for less than half of what we spend to maintain and expand the road system. The shortfall is made up from other sources of tax revenue at the state and local level. This subsidization of car users costs the typical household about $1,100 per year – over and above what they pay in gas taxes, tolls and other user fees."

Report: The Price of Driving Doesn't Match the Cost of Driving

Planetizen: : ""Puncturing the widely held myth that cars pay their own way makes this report required reading for those thinking about transportation finance reform," writes Joe Cortwright."