Cannabis aficionados in 20-plus states and Washington, D.C., will be able to buy marijuana legally for Thursday's high-flying informal holiday known as 4/20. Medicinal use is legal in 38 states.

Why it matters: The legalized marijuana market is worth $64 billion, nearly tripling over the last three years as legalization efforts swept the nation, a Coresight Research report found.

• About two-thirds of marijuana users in Coresight's study said they've increased their drug usage since it was legalized.

By the numbers: 9 out of 10 Americans said marijuana should be legal for medical or recreational use, according to a Pew Research Center survey from October.

• 30% said it should be legal only for medical use.
• Adults in states where weed is legal use it 24% more than in states where it's illegal, a separate study released in August found.

The latest: Kentucky became the 38th state to legalize medical marijuana when Gov. Andy Beshear signed a bill for medicinal cannabis into law on March 31.

• Kentucky's law doesn't officially go into effect until 2025, but Beshear signed an executive order in November allowing for legal possession and use under strict conditions.

Flashback: President Biden announced in October that he would pardon all prior federal offenses of simple marijuana possession and called on governors to pardon simple state possession offenses.

• Voters in two states — Maryland and Missouri — approved legalizing recreational cannabis through ballot initiatives during the midterm elections in November.
• Maryland residents will be able to buy weed from legal recreational dispensaries this summer starting on July 1, Axios' Chelsea Cirruzzo reports.

Meanwhile, in four states — Idaho, Kansas, South Carolina and Wyoming — marijuana is fully illegal, according to DISA Global Solutions, a drug testing company.

• The National Conference of State Legislatures' map of state-regulated cannabis programs shows Georgia, Indiana, Iowa, North Carolina, Tennessee, Texas, Wisconsin and Wyoming allow for low-CBD THC products.
• CBD, or cannabidiol, is an ingredient derived from a non-psychotropic part of the marijuana plant.

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