| Drought Index | Number of months and percent occurrence | |||||
| Extreme | Severe | Moderate | Mild | Normal | Total and % number of drought incidence/probability | |
| SPI-3 | 12 | 27 | 42 | 231 | 526 | 312 (37) |
| SPAI-3 | 19 | 37 | 77 | 286 | 419 | 419 (50) |
| SPI-6 | 15 | 35 | 51 | 308 | 426 | 409 (49) |
| SPAI-6 | 19 | 36 | 77 | 286 | 417 | 418 (50) |
| SPI-12 | 20 | 41 | 49 | 296 | 423 | 406 (49) |
| SPAI-12 | 19 | 41 | 73 | 282 | 414 | 415 (50) |