| Ecological Zone | 1980s Average Rainfall (mm) | 2010s Average Rainfall (mm) |
|---|---|---|
| Southern Sudanian | 940 | 1015 |
| Northern Sudanian | 695 | 760 |
| South Sahelian | 460 | 515 |
| Central Sahelian | 310 | 365 |
| North Sahelian | 175 | 210 |
| Saharan Transition | 85 | 95 |
| Deep Desert | 12 | 18 |
| Hyper-Arid Oasis | 5 | 9 |
Using the table above, calculate the range in average annual rainfall in millimetres (mm) across these ecological zones in the 2010s.