Colorado and Washington, two states that sell marijuana legally, enjoyed hefty sales on the drug in 2016.

Colorado sold more than $1.3 billion worth of marijuana and marijuana products while Washington saw $972 million during its 2016 fiscal year.

The legal sales meant more tax revenue for the states, which brought in $200 million for Colorado.

From Market Watch:

“This money is just the tip of the iceberg. Hopefully this will be a wake-up call for the 42 states that still choose to force marijuana sales into the criminal market and forego millions of dollars in tax revenue,” said Mason Tvert, the Marijuana Policy Project’s Denver-based communications director, in a statement. “The state received nearly $200 million in marijuana tax revenue, whereas just a decade ago it was receiving zero.”

Overall, U.S. marijuana sales grew 30% in 2016, according to data from Arcview Market Research. And using research from cannabis business intelligence and market research firm BDS Analytics, Arcview forecasts cannabis sales will grow at a compound rate of 25%, from $6.7 billion in 2016 to $20.2 billion by 2021.

The Hill reported that the sales also show “evidence of boom times.” Denver hosted a trade show in 2016 that “attracted two thousand vendors and exhibitors.”

California, Maine, Massachusetts, and Nevada legalized recreational marijuana use during the November elections. Alaska, D.C., and Oregon legalized it in 2014. New Jersey, Rhode Island, and Vermont have brought the issue to their respected legislatures during this session.

But all the states have begun to worry since Jeff Sessions has officially taken over as attorney general. As senator, Sessions never kept it a secret his love for the war on drugs:

Sessions is on record in the past saying that “Good people don’t smoke marijuana” and that “marijuana is not the kind of thing that ought to be legalized” and that it is “a very real danger.”

President Barack Obama allowed leeway during his administration, even though the federal government kept marijuana a Schedule 1 drug under the Drug Enforcement Administration.

Those in Colorado fear retaliation from President Donald Trump and Sessions:

“I absolutely believe that the dismantling of cannabis in Colorado would cause a recession,” said Kristi Kelly, the Executive Director of the Marijuana Industry Group.

She says that Colorado has implemented a successful program that other states are modeling, and that any disruptions in the industry would be catastrophic.

“The economics of this are huge in Colorado,” Kelly said. “There is a billion-dollar economic impact in Colorado, which is directly attributable or affiliated with the cannabis industry, so that equates to 20,000 people licensed in trade.”

She says that the cannabis tourism in Colorado and extra taxes have added to Colorado’s boom in recent years and undermined the black market for marijuana.