Nearly three-quarters of Americans are willing to pay increased taxes or tolls to fund roads and other transportation infrastructure, according to a survey from HNTB Corp. to be released on Monday that was seen by Reuters.

The number rises to 84 percent if those tax and toll hikes are mandated by law to be spent only on the infrastructure projects for which they were intended, the survey found.

“People are willing to pay higher taxes and tolls if they knew that the money was going to pay for transportation,” said Kevin Hoeflich, chairman of toll services at HNTB, a Missouri-based engineering firm that designs such projects. “They’ve seen … funding get diverted to other areas and not where they expected.”

At the polls in November, voters in Illinois and New Jersey approved measures that require new revenues from transportation-related fees and taxes to be used exclusively for transportation projects.

The gas tax hike in New Jersey was unpopular and took years to pass, coming only as part of a compromise that also cut sales taxes after Governor Chris Christie halted construction projects when the state’s transportation fund ran dry.

The United States is in the midst of a huge infrastructure backlog. The nation is set to fall $1.44 trillion short of what it needs to spend on infrastructure through the next decade, the American Society of Civil Engineers (ASCE) said last year.

HNTB’s survey found that 73 percent of respondents support public-private partnerships as a way to maintain and build new transportation assets.

Eight in 10 Americans also support adding tolls to existing highways, the survey showed.

Russel Research conducted the poll of 1,027 Americans over 18 years old between July 14 and July 16. The margin of error is plus or minus 3.1 percent.

The willingness to pay is driven largely by the desire to avoid congestion and save time. Survey respondents would pay $1.70 on average to use an express lane if it would save 15 to 30 minutes of travel time, HNTB said.

In January, Reuters released a poll just as President Donald Trump took office promising a $1 trillion infrastructure program that has yet to materialize.

The respondents to that poll, however, expressed little interest in paying for that program, with 51 percent saying they did not want higher taxes as a result.