Before marijuana became legal in some states, you’d have to figure out on your own how much money you’d spend on weed. But now that recreational pot is a-okay in certain areas, it’s much easier to calculate those numbers.

According to a report from Headset Inc., a “cannabis intelligence company,” the average legal pot user is a 37-year-old man who spends around $645 a year on the green stuff, most often choosing buds over edibles and making his purchases every 19.5 or so days.

Millennials are the key audience here, which is unsurprising, with just over 50% of recreational pot consumers aged 21-34.

And where you buy your bud likely depends on your age, Headset found: older folks aren’t quite used to dispensaries, with fewer than 10% of the purchases in the report made by people older than 60. (Probably including that uncle who is always asking younger family members to find him some “wacky tobaccy,” even when your dad is sitting right there at Christmas dinner.)

And although customers in their 20s don’t spend as much each time they visit the dispensary — around $27 per trip — they come back more often than others, at every 16 days.

Who spends the most? Those with the most disposable income — the biggest median annual spenders are users in their 40s, who spent $823 in the last year and those in their 50s, $753.

“As you’re older, you might have more money to go and make bigger purchases,” Headset co-founder Cy Scott told Bloomberg. “The millennials might be out and about more; they can drop into [marijuana dispensaries] more often. Older people might just plan more.”

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