More students in the 12th grade said they smoked pot every day, compared to those who smoke daily cigarettes, finds a new federal report. It's the first time since the survey began in 1975 that daily marijuana use surpassed cigarettes.

The "Monitoring the Future" survey released on Wednesday shows that 6% of 12th graders used marijuana every day—about the same rate as last year—while 5.5% of seniors reported smoking cigarettes daily. (That's a drop from 2014, when 6.7% of high school seniors smoked cigarettes every day.)

Their perceptions of pot also changed; fewer students think it's dangerous. Almost 32% of seniors said they thought regular marijuana use could be harmful, compared to 36% who felt that way last year.