| Population group | Number of participating agencies |
Population covered |
|---|---|---|
| Total | 14,422 | 278,948,317 |
| Group I (Cities 250,000 and over) | 71 | 54,890,728 |
| Group II (Cities 100,000 - 249,999) | 189 | 27,979,415 |
| Group III (Cities 50,000 - 99,999) | 453 | 30,920,847 |
| Group IV (Cities 25,000 - 49,999) | 782 | 26,867,800 |
| Group V (Cities 10,000 - 24,999) | 1,675 | 26,584,452 |
| Group VI1 (Cities under 10,000) | 7,453 | 22,513,367 |
| Metropolitan Counties1 | 1,526 | 64,170,007 |
| Nonmetropolitan Counties1 | 2,273 | 25,021,701 |