Interest in using medical marijuana is far outpacing expectations in Missouri.

The St. Louis Post-Dispatch reports that Missouri has issued close to 22,000 medical marijuana cards in the first five months of the program.

University of Missouri researchers had predicted Missouri wouldn’t reach that many patients until 2021.

The Missouri Medical Cannabis Trade Association estimates that there could be at least 122,000 medical marijuana patients by the end of 2022. Spokesman Jack Cardetti says that estimate is based on trends in states such as Colorado, where 2% to 3% of the population received cards after medical marijuana was approved.

Missouri voters legalized marijuana for medical use in 2018.

The state health department says it plans to start awarding licenses for businesses to grow, dispense and make marijuana-infused products by January.