Colorado’s recreational marijuana stores had their biggest month yet, selling $24.7 million worth of pot in June, a 19 percent increase from the previous month.

Through the first half of 2014, customers from around the world have spent $115 million on recreational marijuana, pouring $20 million in taxes and fees into state and local government coffers.

Medical and recreational pot sales combined for a total of more than $308 million for the year. Medical pot still outpace recreational, but the gap is narrowing. Medical sales fell 10 percent last month to $28.7 million. The patient registry grew slightly in April, and stands at 116,180 approved medical users.

Recreational sales are growing despite a slow roll out of stores. About 120 retail storefronts are now open in Colorado. For comparison, there are more than 500 medical stores in the state.

Denver continues to dominates sales, with customers buying about $54 million in pot in the first half of the year. That’s more than seven times the next-closest county, Boulder, which reported $7 million in pot sales in June.

So far this year, $4 million in taxes are earmarked for school construction, per the constitutional amendment that legalized pot. The excise tax is applied on marijuana transfers from the warehouse to the retail store.