An NEJM account is free. “the proportion reporting having used marijuana in the previous 30 days dropped from 22% to 20% over the same period, and the proportion reporting ever having used marijuana decreased from 39% to 37%.”
The newer the study, the worse it’s looking. I figure it would be a lagging indicator. I don’t particularly like ‘self reporting’ when it comes to sex or drugs though, but it might be the best there is. It certainly hasn’t slowed down any, and the trend is bad.
https://www.nursingcenter.com/journalarticle?Article_ID=4346123&Journal_ID=54030&Issue_ID=4346085
The 2016 Washington State Healthy Youth Survey, which included more than 230,000 students from all counties, reported that despite legalization of marijuana, usage among teens has remained steady. Six percent of eighth graders, 17% of 10th graders, and 26% of 12th graders stated they had used marijuana in the past 30 days, similar to what was reported in the 2014 youth survey. Overall, the use of marijuana among Washington teens has remained stable over the past 10 years.
Evidence exists, however, that fewer teenagers think of marijuana as a risky drug. The Monitoring the Future survey found that 31.1% of 12th graders perceived marijuana as harmful in 2016 compared with 58.3% in 2000.