Insights: Lansing-East Lansing, MI metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 39 over 304 measured days in 2025, which corresponds to a Good band and a Good metro-wide health grade. The monitored-day split lands at 249 Good days (82%), 52 Moderate (17%), and 3 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 57 while the highest single-day reading hit 123 (USG). Metro residents averaged roughly 24.6 clean-air days per 30-day window across the reporting year.

Across the 2020–2025 trend window, good days shifted by -47 and the median AQI moved +2 points, which classifies the multi-year trajectory as stable. The metro avoided any Unhealthy-tier days entirely, an outcome that typically reflects favorable wind patterns, lower industrial density, or effective regional emission controls. Metros with comparable AQI profiles include Beaver Dam, WI (76.4% good, AQI 39); Bennington, VT (82.9% good, AQI 39); Billings, MT (86.7% good, AQI 39).