A state-run survey of 37,000 middle and high school students in Washington state finds that marijuana legalization there has had no effect on youngsters’ propensity to use the drug.

The Washington State Healthy Youth Survey found that the 2016 rate of marijuana use was basically unchanged since 2012, when the state voted to legalize marijuana for recreational use. In the survey, researchers used the measure of “monthly use,” asking students across all grade levels whether they’d used the drug within the past month.

The survey’s numbers show that neither the vote for legalization nor the opening of pot shops in 2014 have had any measurable effect on the rate of marijuana use among teenagers in the state.

Concerns about adolescent pot use have been one of the chief drivers of opposition to legalization campaigns in Washington, Colorado and elsewhere. Attorney General Jeff Sessions recently articulated the view when he told reporters that “I don’t think America is going to be a better place when people of all ages, and particularly young people, are smoking pot.” [Read more at the Denver Post]