Canadians are projected to spend $1 billion on legal marijuana in the final three months of this year after the market opens next month.

Statistics Canada used census data to estimate that 5.4 million people will buy cannabis in the legal market that opens Oct. 17, and another 1.7 million will keep making illicit purchases.

Spending in the legal market will range between $816 million and $1.02 billion in the fourth quarter, the Ottawa-based agency said on Friday. Illegal sales will make up 24 per cent of the market with a range of $254 million to $317 million.

Share prices of marijuana companies are soaring this year, after Prime Minister Justin Trudeau’s government passed legislation to make Canada the first Group of Seven nation to make smoking up legal for adults. Statistics Canada is also preparing to incorporate marijuana sales into its economic growth figures, something Toronto-Dominion Bank says could add as much as $8 billion to gross domestic product.

--With assistance from Erik Hertzberg

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