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. | Dallas County | 84.4 |
| 2. | Harris County | 83.3 |
| 3. | Fort Bend County | 81.0 |
| 4. | Waller County | 80.3 |
| 5. | Titus County | 78.9 |
| 6. | Mitchell County | 77.4 |
| 7. | Potter County | 77.1 |
| 8. | Jefferson County | 77.1 |
| 9. | Castro County | 77.0 |
| 10. | Bell County | 76.9 |
| 11. | Moore County | 76.6 |
| 12. | Tarrant County | 76.5 |
| 13. | Karnes County | 76.5 |
| 14. | Hale County | 75.6 |
| 15. | Brazoria County | 75.6 |
| 16. | Gonzales County | 75.5 |
| 17. | Cochran County | 75.4 |
| 18. | Winkler County | 75.0 |
| 19. | Matagorda County | 74.9 |
| 20. | Howard County | 74.8 |
