LSD

		1976	1977	1978	1979	1980	1981	1982	1983	1984	1985	1986	1987	1988	1989	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004	2005	2006	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2020	2021		2020 - 2021 Change		2016 - 2021 Change	Proportional Change		Peak year - 2021 Change	Proportional Change		Low year - 2021 Change	Proportional Change
Lifetime	8th Grade	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	2.7	3.2	3.5	3.7	4.4	5.1	4.7	4.1	4.1	3.9	3.4	2.5	2.1	1.8	1.9	1.6	1.6	1.9	1.7	1.8	1.7	1.3	1.4	1.1	1.3	1.2	1.3	1.4	1.6	2.1	1.2	\|	-0.9	\|	-0.0	-1.0	\|	-3.9***	-76.3	\|	0.1	9.4
	10th Grade	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	5.6	5.8	6.2	7.2	8.4	9.4	9.5	8.5	8.5	7.6	6.3	5.0	3.5	2.8	2.5	2.7	3.0	2.6	3.0	3.0	2.8	2.6	2.7	2.6	3.0	3.2	3.0	2.8	3.6	3.8	2.5	\|	-1.3**	\|	-0.7	-22.9	\|	-7.0***	-73.9	\|	0.0	0.7
	12th Grade	11.0	9.8	9.7	9.5	9.3	9.8	9.6	8.9	8.0	7.5	7.2	8.4	7.7	8.3	8.7	8.8	8.6	10.3	10.5	11.7	12.6	13.6	12.6	12.2	11.1	10.9	8.4	5.9	4.6	3.5	3.3	3.4	4.0	3.1	4.0	4.0	3.8	3.9	3.7	4.3	4.9	5.0	5.1	5.6	5.9	4.9	\|	-0.9	\|	0.0	0.4	\|	-8.6***	-63.6	\|	1.8*	57.8
Last 12 Months	8th Grade	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	1.7	2.1	2.3	2.4	3.2	3.5	3.2	2.8	2.4	2.4	2.2	1.5	1.3	1.1	1.2	0.9	1.1	1.3	1.1	1.2	1.1	0.8	1.0	0.7	0.9	0.8	0.9	0.9	0.9	1.1	0.7	\|	-0.4	\|	-0.1	-13.7	\|	-2.8***	-80.2	\|	0.0	0.0
	10th Grade	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	3.7	4.0	4.2	5.2	6.5	6.9	6.7	5.9	6.0	5.1	4.1	2.6	1.7	1.6	1.5	1.7	1.9	1.8	1.9	1.9	1.8	1.7	1.7	1.9	2.0	2.1	2.1	2.0	2.3	2.5	1.5	\|	-1.1**	\|	-0.7*	-30.7	\|	-5.4***	-78.5	\|	0.0	1.7
	12th Grade	6.4	5.5	6.2	6.6	6.5	6.5	6.1	5.4	4.7	4.4	4.5	5.2	4.8	4.9	5.4	5.2	5.6	6.8	6.9	8.4	8.8	8.4	7.6	8.1	6.6	6.6	3.5	1.9	2.2	1.8	1.7	2.1	2.7	1.9	2.6	2.7	2.4	2.2	2.5	2.9	3.0	3.3	3.2	3.6	3.9	2.5	\|	-1.4	\|	-0.5	-16.0	\|	-6.3***	-71.2	\|	0.9*	51.1
Last 30 Days	8th Grade	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	0.6	0.9	1.0	1.1	1.4	1.5	1.5	1.1	1.1	1.0	1.0	0.7	0.5	0.5	0.5	0.4	0.5	0.5	0.5	0.6	0.5	0.3	0.5	0.3	0.4	0.4	0.3	0.4	0.4	0.6	0.2	\|	-0.4	\|	-0.2	-43.7	\|	-1.3***	-84.8	\|	0.0	0.0
	10th Grade	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	1.5	1.6	1.6	2.0	3.0	2.4	2.8	2.7	2.3	1.6	1.5	0.7	0.6	0.6	0.6	0.7	0.7	0.7	0.5	0.7	0.7	0.5	0.6	0.6	0.6	0.7	0.8	0.5	1.1	1.0	0.4	\|	-0.7**	\|	-0.3**	-49.0	\|	-2.7***	-88.1	\|	0.0	0.0
	12th Grade	1.9	2.1	2.1	2.4	2.3	2.5	2.4	1.9	1.5	1.6	1.7	1.8	1.8	1.8	1.9	1.9	2.0	2.4	2.6	4.0	2.5	3.1	3.2	2.7	1.6	2.3	0.7	0.6	0.7	0.7	0.6	0.6	1.1	0.5	0.8	0.8	0.8	0.8	1.0	1.1	1.0	1.2	1.0	1.4	1.4	0.5	\|	-0.9**	\|	-0.5*	-47.0	\|	-3.5***	-86.9	\|	0.1	10.9

Source: The Monitoring the Future study, the University of Michigan.

The peak year prevalence is noted in BOLD. The lowest prevalence after the peak is underlined.

* = p < 0.001 = p < 0.01 * = p < 0.05