You can probably guess what it is.
FORTUNE — As the solar industry continues to grow, so do its job opportunities.
It’s no surprise then that the fastest-growing job in the U.S. between 2012 and 2016 was for a solar photovoltaic installers or someone who assembles solar panels on roofs, according to MarketWatch. The job pays about $42,500 a year.
Overall, the U.S. added 211,000 jobs in April. This is an overall increase in employment, but some industries performed better than others, especially the clean energy industry.
The second fastest-growing field was for mathematics and computer jobs, two of the fields that fall under STEM.
The fastest growing job in the country between 2012 to 2016 was a “solar photovoltaic installer” — someone who assembles solar panels on roofs, according to a recent study from personal finance technology company SmartAsset. The rate of growth for this job was 88.3%, jumping from 4,710 in 2012 to 8,870 in 2016, compared to an average of 4.9% for 675 occupations analyzed. It pays an average salary of $42,500 a year, less than the median annual household income of $58,673.
Nationally, mathematics and computer (STEM) occupations were the second-fastest growing field, but only one state in the country had a fastest growing job in that field: Michigan. There, the number of computer and information research scientists increased 200% between 2012 and 2016.
These growing industries may be influencing where people move, too. Delaware, for instance, is losing its college graduates at a rate of 70.9%, a study conducted by career website Zippia found. There, the fastest growing occupation is phlebotomist — a job that does not require a college degree in which technicians draw blood from patients in hospitals and other settings. The state that retained the most college graduates was Texas, with only 20% of its college graduates leaving to find work.
While some careers saw big growth in certain states, their relatively low pay may have kept people from relocating there. The number of record-keepers in Nevada, for example, grew 176% between 2012 and 2016 but only made an average income of $27,610. In Georgia, food and tobacco roasting, baking, and drying machine operators grew 340% from 2012 to 2016 but with a salary of $27,000 per year.
Other industries that saw growth include personal care, which despite a relatively low salary is booming. In Utah, for example, the number of personal care aids increased 313% to 6,780 jobs. Its average salary is 21,890 per year. In North Carolina, the number of skincare specialists, which have an average salary of $33,760, grew 187% to 890 positions.
Zippia also found gender plays a role in whether people move for their first jobs. It found men move on average 16% farther than women for their first jobs after graduation. This varied by major — women with STEM degrees, for example moved significantly more. This could be because the pay gap is lower within the STEM field, so perhaps they have more of an incentive to relocate, said David Luther, a content creator at Zippia.