"By combining the data from 2012 and 2013, we can obtain more precise estimates of prevalence levels for cannabis use and differences between subgroups. The estimated LTP [lifetime prevalence], LYP [last year prevalence] and LMP [last month prevalence] rates among all adults (aged 16–64) were 21.3 per cent, 4.3 per cent and 1.6 per cent, respectively. Among young adults (aged 16–34), the corresponding LTP, LYP and LMP estimates are 30.2 per cent, 10 per cent and 3.4 per cent.

"There are significant gender differences in cannabis use, with males having higher prevalence rates than females. Using the combined data from 2012 and 2013 for all adults, the estimated LTP rate was 25.9 per cent for males and 16.6 per cent for females, while the LYP rate was 6.1 per cent for males and 2.4 per cent for females and the LMP rate was 2.5 per cent for males and 0.7 per cent for females. Among young adults, the estimated LTP rate was 36.2 per cent for males and 23.5 per cent for females, while LYP was 13.9 per cent for males and 5.8 per cent for females and LMP was 5.1 per cent for males and 1.4 per cent for females (all gender differences were significant at p<.05).

"Cannabis use also varies across age groups (Figure 2). Both LYP and LMP rates decline with age. The LYP rate was estimated to be 12.1 per cent for persons in the 16–24 age group, 7.9 per cent in the 25–34 age group and around one per cent or less in the three oldest age groups (35–44, 45–54 and 55–64). The LMP rate was 4.2 per cent in the 16–24 age group, 2.4 per cent in the 25–34 age group and less than one per cent in the three oldest age groups. Even though the biggest differences are between the youngest and the three oldest age groups in relation to both LYP and LMP, the LYP rate in the 25–34 age group is significantly lower (p<.05) than in the 16–24 age group."

Source

Drug Situation in Norway 2014, Norwegian Institute for Alcohol and Drug Research (SIRUS)/EMCDDA. Statistics 2015. ISBN: 978-82-7171-422-2. Available at www.fhi.no/en
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