"The most recent data shows that drug producers continue to create new substances to avoid legal controls, although the rate at which new psychoactive substances are now entering the market appears to be slowing. Between 2016 and 2022, typically around 50 new psychoactive substances appeared on the market for the first time each year; this fell to 26 in 2023. In addition, around 400 previously reported new substances are detected on the market each year."

Source

European Monitoring Centre for Drugs and Drug Addiction (2024), European Drug Report 2024: Trends and Developments.