The number of good air quality days in 367 Chinese cities (2014–2024)

According to China’s Air Quality Standard (GB 3095-2012), an Air Quality Index (AQI) of ≤50 is classified as excellent, ≤100 as good, ≤150 as light pollution, ≤200 as moderate pollution, ≤300 as heavy pollution, and >300 as severe pollution. Using daily data from the China National Environmental Monitoring Center, we have compiled a dataset tracking the annual number of good air quality days (i.e., days with AQI ≤100) across 367 cities in China from 2014 to 2024. This dataset serves as a valuable resource for assessing and analyzing urban environmental quality.