01/19/2017 08:30 EST

Legal Marijuana Spending Could Grow To $21 Billion By 2021

And that number's only predicted to increase.

Canadians and Americans spent US$56.4 billion on marijuana in 2016, and 88 per cent of that spending was illegal, according to a new report.

The report by ArcView Market Research, titled "The State Of Legal Marijuana Markets," looked at legal, medicinal and illicit markets in the U.S. and Canada. The organization released an executive summary of their findings this week, in advance of the full report's release in February.

Legal spending constituted US$6.9 billion of last year's total, which is up 34 per cent from 2015. The organization predicts that number could grow to US$21.6 billion by 2021, thanks to projected sales increases in Canada, California and Massachusetts. However, it does note that is based on the assumption that the U.S. "does not return to waging all-out war on the cannabis industry."

Marc Emery, Canada's self-proclaimed 'Prince of Pot,' and founder of the Cannabis Culture dispensary chain,is seen in his illegal recreational cannabis storefront in Montreal, Que. (Photo: Julien Besset/AFP/Getty)

In 2016, seven U.S. states voted in favour of different forms of legality. Canada reaffirmed its intent to legalize marijuana in 2017, while Mexico voted to send a medical legalization bill to the Chamber of Deputies.

One of the biggest areas for financial growth was in Colorado, where retail sales grew from US$675 million in 2014, to over US$1.3 billion in 2016.

ArcView wrote that the only thing holding the cannabis industry back is its legality.

"In contrast to comparable markets which quickly grew from zero to tens of billions of dollars, such as organic foods, home video, cell phone, or the internet, the cannabis industry doesn’t need to create demand for a new product or innovation — it just needs to move demand for an already widely popular product into legal channels."

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