Green Book
PM-2.5 (2006) Nonattainment Area Summary
As of September 22, 2016| Classification | Number of Areas | Number of Counties | 2010 Population |
| Serious | 2 | 12 | 19,558,407 |
| Moderate | 14 | 34 | 12,780,620 |
| SUBTOTAL | 16 | 46 | 32,339,027 |
| GRAND TOTAL | 16 | 46 | 32,339,027 |
County subtotals and grand totals may not equal sum of parts. Part counties are only counted one time within groupings. Multi-state nonattainment areas are not considered maintenance areas until all states in the area have been redesignated