| Authors | Regions | M (yr−1) | F (yr−1) | Z (yr−1) |
| Villanueva (2004) [2] | Ivory Coast | 1.421 | 0.138 | 1.559 |
| Villanueva (2004) [2] | Gambia | 0.991 | 0.518 | 1.509 |
| Valiky and Cham (2003) [13] | Sierra Leone | 1.8 | - | 5.1 |
| StokholmandIsebor (1993) [43] | Benin et Nigeria | - | - | 3.66 |