Academics have long known that many state occupational licensing standards are onerous. To become a barber in Nevada, for instance, you will have to pass four examinations, pay a $140 fee and spend nearly two-and-a-half years in classes and apprenticeship. In fact, Alabama is the only state that does not have occupational licensing requirements for barbers. All to cut hair!

It would make sense that poor Americans in Alabama have an easier time becoming a barber than those in Nevada do. Now, we have the data to back that up. In a soon-to-be-published paper, Stephen Slivinski, a senior economist at the Goldwater Institute, finds that states with strict occupational licensing standards have lower levels of low-income entrepreneurship.

Slivinski used two different data sets, one from the Kaufmann Institute on low-income entrepreneurship and a second from the Institute for Justice on occupational licensing standards. The former compares a state’s number of low-income entrepreneurs—people who are self-employed like many barbers or taxi drivers—with its low-income population. By that metric, Colorado has the most low-income entrepreneurs; 7.5 of every 1,000 low-income Coloradoans report that they are self-employed. Mississippi has the fewest with just one out of every 1,000.

Slivinski then used the Institute for Justice data to see how many, out of 51 low-income occupations, states license. For instance, Louisiana licenses 41 of those 51 jobs, the highest rate in the country. Five different states—Indiana, Kentucky, Ohio, South Dakota, and Vermont—tie for the least restrictive occupational licensing regimes, with licensing requirements for just eight of the 51 low-income occupations.

He then compared each state’s rate of low-income entrepreneurship with the percentage of low-income occupations licensed there, while controlling for other explanatory factors like the percentage of the male population and percentage of the state’s population that is Hispanic/Latino. It was particularly important to control for the latter variable because low-income entrepreneurs, it turns out, are disproportionately more likely to be Hispanic or Latino. That means states with high populations of Hispanics and Latinos were likely to have higher rates of low-income entrepreneurship, regardless of the occupational licensing standards.