Proponents of legalizing and regulating recreational marijuana received some good news Tuesday, as a new market research study pegged the total value of legal North American sales of the drug in 2016 at $6.7 billion. That was a 30 percent rise over the previous year, according the report obtained by Forbes. In the U.S. alone, sales were $5.86 billion, the report found.

The study was conducted by ArcView Market Research, which, it may be worth noting, estimated in February that U.S. sales in 2016 would reach $6.7 billion, nearly $1 billion less than the actual total. A 25 percent compound annual growth rate for the legal weed market was also forecast. The North American weed market’s value could climb to $20.2 billion by 2021, a bit less than the company’s previous expectations of a $21.8 billion U.S. market value for the year 2020.

Tom Adams, the editor-in-chief of the San Francisco-based cannabis market research firm, compared the industry’s rapid growth to the dotcom bubble of the early aughts.

“The only consumer industry categories I’ve seen reach $5 billion in annual spending and then post anything like 24 percent compound annual growth in the next five years are cable television (19 percent) in the 1990s and the broadband internet (29 percent) in the 2000s,” Adams said in the report, according to Forbes.

Hes not the only one comparing the market for legal weed to the sources of past market bubbles.

While publicly traded marijuana companies in the U.S. operate mostly on the peripheries, due to the substance’s illegality at the federal level, Canada’s legalization of medicinal marijuana possession and production and expectations for full legalization in 2017 have led to a surge in valuation of the country’s 26 publicly traded marijuana stocks, to the equivalent of $3 billion (USD) from almost nothing as recently as the past summer.

“Oh, they’re going to pop,” Nick Brusatore, the largest holder of shares in Affinor Growers Inc., told Bloomberg in December, referring to the market bubble. “It’s going to pop hard.”