| 年份 | 尼日利亚 |
|---|---|
| 2023 | - |
| 2022 | - |
| 2021 | 5.237 |
| 2020 | 5.309 |
| 2019 | 5.379 |
| 2018 | 5.447 |
| 2017 | 5.523 |
| 2016 | 5.584 |
| 2015 | 5.616 |
| 2014 | 5.664 |
| 2013 | 5.738 |
| 2012 | 5.832 |
| 2011 | 5.918 |
| 2010 | 5.98 |
| 2009 | 6.039 |
| 2008 | 6.078 |
| 2007 | 6.08 |
| 2006 | 6.081 |
| 2005 | 6.068 |
| 2004 | 6.085 |
| 2003 | 6.116 |
| 2002 | 6.135 |
| 2001 | 6.139 |
| 2000 | 6.124 |
| 1999 | 6.082 |
| 1998 | 6.069 |
| 1997 | 6.138 |
| 1996 | 6.217 |
| 1995 | 6.273 |
| 1994 | 6.319 |
| 1993 | 6.354 |
| 1992 | 6.391 |
| 1991 | 6.426 |
| 1990 | 6.459 |
| 1989 | 6.494 |
| 1988 | 6.498 |
| 1987 | 6.504 |
| 1986 | 6.557 |
| 1985 | 6.616 |
| 1984 | 6.701 |
| 1983 | 6.775 |
| 1982 | 6.799 |
| 1981 | 6.82 |
| 1980 | 6.847 |
| 1979 | 6.887 |
| 1978 | 6.921 |
| 1977 | 6.862 |
| 1976 | 6.806 |
| 1975 | 6.773 |
| 1974 | 6.703 |
| 1973 | 6.633 |
| 1972 | 6.579 |
| 1971 | 6.532 |
| 1970 | 6.466 |
| 1969 | 6.438 |
| 1968 | 6.42 |
| 1967 | 6.401 |
| 1966 | 6.386 |
| 1965 | 6.367 |
| 1964 | 6.362 |
| 1963 | 6.349 |
| 1962 | 6.356 |
| 1961 | 6.353 |
| 1960 | 6.364 |