Story highlights Colorado marijuana shops have surpassed $1 billion in sales this year

Sales are expected to reach $1.3 billion by the end of 2016

(CNN) It's always 4/20 somewhere — at least in Colorado. The state's marijuana shops have reached a massive new milestone: $1 billion in legal, regulated sales in the first 10 months of 2016.

Voters legalized marijuana in Colorado back in 2012 , but the dispensaries didn't open until 2014 Last year , the marijuana industry created 18,000 full-time jobs and generated $2.39 billion in economic activity in the state.

And the boom is still growing. According to new data from the state's Department of Revenue , recreational and medical cannabis shops have sold more than $1 billion of marijuana and related products so far in 2016, already surpassing last year's total of $996,184,788.

Attorney Christian Sederberg, partner at Vicente Sederberg, played an integral part in Colorado's Amendment 64, which legalized marijuana in the state. He is estimating that sales of pot will reach $1.3 billion by the end of this year, which could have a total economic impact of over $3 billion.

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"This milestone continues to show that the cannabis industry in Colorado is an engine of growth for the economy, a job creator, and one of the biggest industries in the state," Sederberg told CNN. "People were consuming cannabis before, but now they are buying it from tax-regulated businesses that are benefiting the economy. This has replaced an underground, illegal market."

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