| 年份 | 尼日利亚 |
|---|---|
| 2023 | - |
| 2022 | 2.38001 |
| 2021 | 2.40636 |
| 2020 | 2.44061 |
| 2019 | 2.4482 |
| 2018 | 2.49664 |
| 2017 | 2.52732 |
| 2016 | 2.50703 |
| 2015 | 2.54119 |
| 2014 | 2.62812 |
| 2013 | 2.69747 |
| 2012 | 2.74929 |
| 2011 | 2.76406 |
| 2010 | 2.74438 |
| 2009 | 2.72738 |
| 2008 | 2.71969 |
| 2007 | 2.70963 |
| 2006 | 2.69593 |
| 2005 | 2.69369 |
| 2004 | 2.6955 |
| 2003 | 2.69277 |
| 2002 | 2.68289 |
| 2001 | 2.65127 |
| 2000 | 2.60287 |
| 1999 | 2.54262 |
| 1998 | 2.51603 |
| 1997 | 2.52296 |
| 1996 | 2.52685 |
| 1995 | 2.55719 |
| 1994 | 2.57483 |
| 1993 | 2.55577 |
| 1992 | 2.52373 |
| 1991 | 2.5622 |
| 1990 | 2.6286 |
| 1989 | 2.61364 |
| 1988 | 2.58684 |
| 1987 | 2.5771 |
| 1986 | 2.62007 |
| 1985 | 2.72593 |
| 1984 | 2.47194 |
| 1983 | 2.50558 |
| 1982 | 2.90087 |
| 1981 | 3.00299 |
| 1980 | 3.06371 |
| 1979 | 3.03784 |
| 1978 | 3.02292 |
| 1977 | 2.94325 |
| 1976 | 2.83449 |
| 1975 | 2.73123 |
| 1974 | 2.57126 |
| 1973 | 2.43113 |
| 1972 | 2.32373 |
| 1971 | 2.25681 |
| 1970 | 2.19879 |
| 1969 | 2.13938 |
| 1968 | 2.09554 |
| 1967 | 2.10697 |
| 1966 | 2.16856 |
| 1965 | 2.16539 |
| 1964 | 2.13863 |
| 1963 | 2.11478 |
| 1962 | 2.08546 |
| 1961 | 2.04265 |
| 1960 | - |