In 2012, citizens in the US sate of Washington voted to legalize marijuana.
In order to determine the amount of licenses needed to produce pot, state officials estimate that 80 million marijuana joints would be used each year. The estimated number of users in the state is roughly calculated to be 650,000 adults. Thus, an average pot user in the state of Washington consumes 123 joints each year, or one joint every three days.
Despite the legal market, state officials estimate that the regulated market will capture about 25 percent of the total marijuana market in the state, leaving 75 percent of sales still taking place on the black market.
Source: Bob Young, “Average pot user consumes 123 joints per year, state estimates,” Seattle Times, September 24, 2013.