From Monitoring the Future 2015: http://monitoringthefuture.org//pressreleases/15drugpr_complete.pdf
Nationally, the percentage of youth saying they have used heroin showed a slight decline (.05%) in 2015. The national average for heroin use has dropped from 1.0 percent in 2000 to .05% in 2015. The improvements this year were almost entirely in taking heroin using a needle–the most dangerous form of use. There was little change in the prevalence of taking heroin without using a needle. This decide in heroin use was not accompanied by an increase in the use of other narcotic drugs. Past year use of narcotic drugs other than heroin (reported only for grade 12) did not show any increase as heroin declined. In fact, annual prevalence fell from 6.2% to 5.4% in 2015 and from an annual prevalence of 9.2% in 2009.