Heavy and tractor-trailer truck drivers and first-line supervisors of retail sales workers top CareerBuilder’s list of the most in-demand jobs for 2018 that do not require a college degree.

The list is comprised of occupations where the number of job ads companies post each month outpace the number of people they actually hire, and includes other data points such as job growth and salary. The study is based on data from Emsi, CareerBuilder’s labor market analysis arm.

The top five occupations that don’t typically require a college degree and have the largest gap between job openings and hires are:

1. Heavy and tractor-trailer truck drivers: Gap of 1,555,003 jobs
2. First-line supervisors of retail sales workers: Gap of 192,033 jobs
3. Food service managers: Gap of 40,710 jobs
4. Insurance sales agents: Gap of 39,920 jobs
5. Computer user support specialists: Gap of 24,287 jobs

“When people think of skills gaps, they typically think of high-skill tech or healthcare jobs that require advanced degrees,” CareerBuilder CEO Matt Ferguson said. “The reality is those gaps are being felt across all types of roles, including a wide range of jobs that don’t necessarily require a college education. What employers will look for first is whether candidates have the core competencies to fill their open positions, and those competencies can be developed in different ways outside of a formal classroom.”

The study is based on data from Emsi, which aggregates information from multiple national and local employment resources. CareerBuilder and Emsi looked at the average number of people hired per month in more than 700 occupations from January 2017 to August 2017 and compared that to the number of job postings for each occupation (aggregated from online job sites for the same period).