President Donald Trump’s $200 billion infrastructure plan lacks specifics but the promise of “gleaming new roads, bridges, highways, railways and waterways” across America would certainly spur growth for those who work in construction.

There are 27 occupations within the sector, according to the U.S. Bureau of Labor Statistics. So which are the most lucrative?

Elevator installers and repairers top the list, making a median annual income of $80,000. This is more than three times the salary of the least paid — construction helpers (who make an average $22,000 a year).

Using Bureau of Labor Statistics data, BuildZoom, a service that helps folks find licensed contractors, analyzed the wide spectrum of professions within the construction industry. The company cites “the high-rise boom propelled by demand for offices and residential towers across U.S. cities” as the primary reason that elevator technicians are getting the best compensation. BLS projects that employment of elevator technicians will grow 12% from 2016 to 2026, faster than the average for all occupations.

Of course, it’s not a glamorous profession by any means. As the BLS describes, elevator installers “often work in cramped quarters inside crawl spaces and machine rooms, and may be exposed to heights in elevator shafts. Repairers may be required to work overtime when essential equipment needs repair and are sometimes on call 24 hours a day.”

Who else tops the list?

Supervisors of construction and extraction workers come in a distant second, earning an average of $58,000 a year. Boilermakers and building inspectors, who make an average of $55,000, are tied for third.

“Not every occupation in the construction industry entails physical labor; supervisors manage workers, structural engineers use engineering skills to determine the integrity of a structure, and building inspectors review plans to assess its compliance with building codes,” the report points out.

A common misconception may be that white-collar jobs should rake in more income, but the data indicates that jobs involving tough, physical labor are some of the highest paid.

“Occupations that require more training or technical expertise consistently pay higher than those with lower barriers to entry,” said BuildZoom’s Chief Economist Issi Romem. Construction helpers, roofers, plasterers, and painters are the lowest paid jobs in the industry. Those types of workers make, on average, less than $30,000 a year.

Where you earn the most (and least)

Wages for the construction industry vary significantly across the country. BuildZoom compared the six most common construction trades — supervisors, electricians, plumbers, carpenters, construction laborers and painters — to examine which cities offer the highest pay.