The Diversity Index is a scale of 0 to 100 that represents the likelyhood that two persons, chosen at random from the same area, belong to different race or ethnic groups. If an area's entire population belongs to one race AND one ethnic group, then the area has zero diversity. An area's diversity index increases to 100 when the population is evenly divided into two or more race/ethnic groups.
| County | Diversity Index | |
|---|---|---|
| 1. | Lewis County | 9.8 |
| 2. | Hamilton County | 11.3 |
| 3. | Schuyler County | 11.6 |
| 4. | Yates County | 12.6 |
| 5. | Tioga County | 12.7 |
| 6. | Chenango County | 12.8 |
| 7. | Allegany County | 13.2 |
| 8. | Herkimer County | 13.2 |
| 9. | Steuben County | 14.2 |
| 10. | Oswego County | 14.7 |
| 11. | Warren County | 15.2 |
| 12. | Madison County | 15.7 |
| 13. | Schoharie County | 15.9 |
| 14. | Cortland County | 16.8 |
| 15. | Fulton County | 17.3 |
| 16. | Essex County | 17.8 |
| 17. | Washington County | 17.9 |
| 18. | St. Lawrence County | 18.2 |
| 19. | Delaware County | 19.0 |
| 20. | Otsego County | 20.1 |
