The rate of 12th grade students who reported lifetime abstinence from substance use increased from 5% in 1976 to 26% in 2014, and the rate of those who said they didn't have any substance use within the previous month rose from 23% to 52%.

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The rate of 12th grade students who reported lifetime abstinence from substance use increased from 5% in 1976 to 26% in 2014, and the rate of those who said they didn't have any substance use within the previous month rose from 23% to 52%.