Table 2.
Prevalence of self-reported past-year marijuana use in adults in the USA, by selected demographic factors, NHANES 2005–2018
| 2005–2006 | 2007–2008 | 2009–2010 | 2011–2012 | 2013–2014 | 2015–2016 | 2017–2018 | P value | |
| Prevalence % (95% CI) | Prevalence % (95% CI) | Prevalence % (95% CI) | Prevalence % (95% CI) | Prevalence % (95% CI) | Prevalence % (95% CI) | Prevalence % (95% CI) | ||
| Age | ||||||||
| 18–29 | 34.0* (26.7 to 42.0) | 35.1 (30.0 to 40.6) | 34.4 (30.7 to 38.3) | 36.2 (31.7 to 41.1) | 38.1 (35.1 to 41.2) | 37.3 (30.4 to 44.8) | 46.3 (42.5 to 50.2) | 0.001† |
| 30–49 | 16.1 (12.3 to 20.7) | 16.2 (14.3 to 18.2) | 17.5 (14.7 to 20.7) | 17.0 (14.4 to 20.1) | 16.3 (13.8 to 19.1) | 21.1 (16.0 to 27.3) | 24.6 (20.6 to 29.1) | 0.001 |
| 50–69 | 10.5 (7.4 to 14.6) | 8.1 (6.0 to 10.9) | 10.3 (7.8 to 13.4) | 15.5 (11.4 to 20.8) | 14.3 (9.2 to 21.5) | 18.0 (13.0 to 23.7) | 17.0 (12.4 to 22.8) | <0.001 |
| <0.001‡ | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | ||
| Gender | ||||||||
| Male | 24.8 (20.3 to 29.9) | 23.1 (20.8 to 25.7) | 24.8 (22.0 to 27.8) | 27.3 (24.6 to 30.1) | 26.3 (23.2 to 29.7) | 29.2 (23.1 to 36.3) | 32.0 (28.6 to 35.6) | 0.001 |
| Female | 13.6 (10.1 to 18.1) | 15.1 (13.1 to 17.3) | 16.3 (13.6 to 19.3) | 17.3 (14.0 to 21.2) | 18.2 (15.3 to 21.6) | 20.6 (16.5 to 25.4) | 26.3 (22.1 to 31.0) | <0.001 |
| <0.001 | <0.001 | <0.001 | <0.001 | 0.001 | <0.001 | 0.02 | ||
| Race | ||||||||
| NH White | 20.1 (15.6 to 25.7) | 19.4 (17.7 to 21.3) | 21.1 (18.4 to 24.1) | 22.7 (19.4 to 26.3) | 22.0 (18.3 to 26.3) | 26.7 (20.4 to 34.1) | 30.0 (25.5 to 34.5) | <0.001 |
| NH Black | 23.56 (18.4 to 29.1) | 26.9 (22.6 to 31.7) | 27.6 (24.6 to 30.9) | 27.3 (22.1 to 33.2) | 32.9 (29.8 to 36.1) | 32.5 (28.8 to 36.5) | 36.8 (32.5 to 41.3) | <0.001 |
| Hispanic/Mexican | 11.7 (8.3 to 16.2) | 13.6 (9.8 to 18.5) | 16.6 (13.0 to 20.9) | 18.9 (15.2 to 23.2) | 17.9 (15.5 to 20.6) | 16.3 (13.1 to 20.2) | 25.0 (22.2 to 28.1) | <0.001 |
| Other | 13.2 (7.9 to 21.2) | 13.3 (7.5 to 22.6) | 12.7 (7.4 to 21.1) | 18.7 (14.2 to 24.1) | 18.0 (13.7 to 23.3) | 19.9 (13.3 to 28.7) | 22.9 (18.3 to 28.3) | 0.003 |
| 0.003 | 0.002 | <0.001 | 0.06 | <0.001 | 0.001 | 0.002 | ||
| Education | ||||||||
| <High school | 22.5 (16.5 to 30.0) | 22.1 (17.6 to 27.3) | 23.3 (19.5 to 27.6) | 27.5 (22.6 to 33.0) | 27.9 (23.6 to 32.6) | 24.7 (20.0 to 30.1) | 27.8 (23.3 to 32.8) | 0.06 |
| High school | 21.6 (15.1 to 30.0) | 19.6 (17.5 to 21.8) | 24.7 (21.2 to 28.5) | 25.8 (20.8 to 31.5) | 25.4 (21.1 to 30.3) | 27.5 (22.3 to 33.4) | 34.1 (28.1 to 40.6) | <0.001 |
| >High school | 17.4 (13.2 to 22.7) | 18.0 (15.4 to 20.8) | 18.2 (15.1 to 21.9) | 20.2 (17.2 to 23.4) | 19.8 (16.9 to 23.0) | 24.1 (18.2 to 31.3) | 27.1 (23.4 to 31.2) | <0.001 |
| 0.25 | 0.21 | 0.006 | 0.01 | 0.01 | 0.42 | 0.05 | ||
| Poverty | ||||||||
| >2x PL | 17.7 (13.5 to 22.8) | 16.3 (14.4 to 18.5) | 17.1 (14.2 to 20.5) | 18.3 (15.6 to 21.3) | 18.5 (15.7 to 21.6) | 22.4 (17.3 to 28.4) | 26.3 (22.2 to 30.8) | 0.001 |
| 1–2x PL | 22.0 (16.4 to 28.8) | 24.5 (20.8 to 28.6) | 22.4 (18.0 to 27.7) | 27.9 (23.8 to 32.3) | 25.3 (21.6 to 29.5) | 29.4 (21.8 to 38.4) | 32.1 (28.3 to 36.2) | 0.002 |
| <PL | 24.3 (19.2 to 30.2) | 25.2 (19.5 to 32.0) | 34.6 (30.9 to 38.6) | 31.1 (27.1 to 35.4) | 33.2 (28.3 to 38.6) | 29.8 (23.6 to 37.0) | 37.0 (32.2 to 42.1) | 0.002 |
| 0.05 | 0.001 | <0.001 | <0.001 | <0.001 | 0.004 | 0.001 | ||
Prevalence percentage with 95% CIs, computed using 2-year interview weights to provide estimates for the total US population and are age standardised to the US 2000 Census population.
*Percentage interpretation: of those aged 18–29, 34% reported marijuana use within the past 12 months. Poverty defined using poverty income ratio, accounting for family size.
†P values test overall trend in prevalence estimates in each category.
‡P values test global within group differences in prevalence.
NH, non-Hispanic; NHANES, National Health and Nutrition Examination Survey; PL, poverty level.