* Although preliminary annual statistics are continually released, SAGE Stats only provides final statistics, which are released in May of the following year. Report includes exceptional events; these events (such as wildfires) are not "reasonably controllable" and are hence excluded from assessments relating to air quality regulation, but they nevertheless affect air quality.
Years Available: 2000–2019
Permanent Link: http://data.sagepub.com/sagestats/4027
General Notes: *Median value shows the 50th percentile of counties reporting data to the Air Quality Statistics (AQS)Data Mart; it is not reflective of the entire country. **Computed by AQS software for each hour of the day as a moving average of eight 1-hour values. Second-highest non-overlapping 8-hour values in the year, in parts per million by volume (ppm). Non-overlapping means that the 8-hour averages do not include any of the same 1-hour values.