As the U.S. Congress considers raising the federal gas tax rate, a question underlying the discussion is whether Americans will support a tax increase. Researchers from the Mineta Transportation Institute (MTI) conducted their ninth annual public opinion survey on this topic: “What Do Americans Think about Federal Tax Options to Support Transportation? Results From Year Nine of a National Survey.” Results indicate that a majority of Americans would support higher taxes for transportation — given the right conditions. For instance, 72% of respondents supported a gas tax increase of 10 cents per gallon to improve road maintenance, whereas support dropped to just 34% if the revenues were to be used “for transportation” more generally.

The survey is the ninth in an annual series that asks the same questions each year. This year’s results continue the trend of gradually rising support for increase in the gas tax rate. Since 2010, support for each gas tax option has grown by 10 to 15 percentage points.

The survey also found support has grown for a “green” mileage fee option. Support has grown from 33% in 2010 to 46% this year. In this scenario, drivers would pay an average of a penny per mile driven, but the rate would be lower for vehicles that pollute less and higher for vehicles that pollute more.

“We face growing needs across our transportation system, but funding hasn’t kept pace,” says Dr. Asha Weinstein Agrawal, one of the study authors and Director of MTI’s National Transportation Finance Center. “To solve this dilemma, we must either lower our goals for system maintenance and improvements, or raise new revenues.”

The survey tested public support for ten different tax options: seven variants of a gas tax increase, two variants of a new mileage tax, and one new sales tax option.

Key 2018 findings include:

• Six of the 10 transportation options tested had majority support.

• Linking tax increases to safety, maintenance, or environmental benefits increased support by at least 10 percentage points among almost every sociodemographic group.

• Since 2010, support for the taxes has increased.