(Business Insider) Recreational cannabis sales are set to begin in California on January 1 — and the market is expected to haul in billions in revenue next year as dispensaries roll out across the state.

A report from the cannabis industry research firm BDS Analytics estimates sales of cannabis to hit $3.7 billion in 2018 alone, and predict that number will increase to $5.1 billion in 2019 as more dispensaries come online.

For comparison, beer sales in California hit $5 billion in 2017, according to industry research group IBIS World.

Note: Read our discussion guidelines before commenting.