Cannabis use among Canadians aged 15 and older more than doubled over the past three decades, according to a new study by Statistics Canada.

The study, released Wednesday, compared nine national household surveys that collected data about pot consumption from 1985 to 2015.

An analysis of the data showed that cannabis use among those who are 15 and older more than doubled from 5.6 per cent in 1985 to 12.3 per cent in 2015.

The surveys used for the study included the Canadian Tobacco, Alcohol and Drugs Survey and the 1985 Health Promotion Survey. StatsCan says that each survey asked participants about their pot use within the past year and had “target populations,” such as youth and adults.

Data collected between 2004 and 2015 suggest that cannabis use decreased among some age groups but increased among others.

For example, pot use decreased among females between the ages of 15 and 17, as well as all adults between the ages of 18 and 24. But cannabis use increased among those 25 and older during the same time period.

The most recent data from 2015 show that cannabis use was highest among those aged 18 to 24 (28.4 per cent), followed by the 15 to 17 age group (18 per cent).

Statistics Canada says this latest study is part of its efforts to “measure the social and economic impacts of legalized cannabis” as marijuana legalization is expected sometime next summer.