Another legalization fear goes up in smoke.

Teen marijuana use in Washington has trended down since recreational use was legalized for adults, according to the state’s latest Healthy Youth Survey, driving a data-supported stake through the heart of one of the biggest anti-legalization talking points: That recreational product would find its way to non-adult consumers.

In the fall of 2016, marijuana use was self-reported by 6% of eighth graders (down from 8% in 2014), 17% of 10th graders (down from 18%), and 26% of 12th graders (down from 28%).

Further, over the same span the “perceived ease of obtaining marijuana ” remained stable among 8th and 12th graders, and declined among 10th graders (from 32% to 27%).

More than 230,000 students from all 236 Washington school districts participated in the survey, which is a joint effort conducted by all the parties you’d hope for in an impartial study: the Office of the Superintendent of Public Instruction, the Department of Health, the Department of Social and Health Service’s Division of Behavioral Health and Recovery, the Liquor and Cannabis Board, and the Department of Commerce.