| REGION | 1990-95 | 1995-2000 | 2000-05 | 2005-10 | 2010-15 | 2015-20 | 2020-25 |
| AFRICA | 4.94 | 4.72 | 4.48 | 4.21 | 3,85 | 3.43 | 3.05 |
| EASTERN AFRICA | 6.41 | 5.94 | 5.44 | 5.12 | 4.72 | 4.24 | 3.74 |
| MIDDLE AFRICA | 5.07 | 4.98 | 4.83 | 4.56 | 4.21 | 3.75 | 3.24 |
| NORTHERN AFRICA | 3.92 | 3.66 | 3.40 | 3.08 | 2.71 | 2.36 | 2.18 |
| SOUTHERN AFRICA | 3.49 | 3.29 | 3.04 | 2.79 | 2.53 | 2.26 | 1.97 |
| WESTERN AFRICA | 5.32 | 5.12 | 4.90 | 4.59 | 4.12 | 3.62 | 3.16 |