PULLMAN, Wash. – New research at Washington State University says marijuana use among teens has gone down since retail sales were legalized in Washington state.

The research found that marijuana use “went down significantly” among eighth- and tenth-graders after legalization, and among 12th-graders who did not have a job. The researchers defined a job as anything that did not include household chores, yardwork and/or babysitting.

Only high school seniors who worked 11 or more hours per week were found to have increased marijuana usage after legalization. Usage stayed nearly even for seniors who worked less than 11 hours per week.