| 年份 | 尼日尔 |
|---|---|
| 2023 | - |
| 2022 | 4.50447 |
| 2021 | 4.54391 |
| 2020 | 4.58493 |
| 2019 | 4.61893 |
| 2018 | 4.6452 |
| 2017 | 4.65845 |
| 2016 | 4.65402 |
| 2015 | 4.63747 |
| 2014 | 4.61926 |
| 2013 | 4.60575 |
| 2012 | 4.59836 |
| 2011 | 4.60178 |
| 2010 | 4.61839 |
| 2009 | 4.64581 |
| 2008 | 4.68513 |
| 2007 | 4.7362 |
| 2006 | 4.79549 |
| 2005 | 4.85817 |
| 2004 | 4.9217 |
| 2003 | 4.98239 |
| 2002 | 5.03529 |
| 2001 | 5.07896 |
| 2000 | 5.11514 |
| 1999 | 5.14351 |
| 1998 | 5.16333 |
| 1997 | 5.17733 |
| 1996 | 5.1853 |
| 1995 | 5.18444 |
| 1994 | 5.17739 |
| 1993 | 5.16808 |
| 1992 | 5.15726 |
| 1991 | 5.14344 |
| 1990 | 5.12508 |
| 1989 | 4.96622 |
| 1988 | 4.69714 |
| 1987 | 4.49351 |
| 1986 | 4.3427 |
| 1985 | 4.22458 |
| 1984 | 4.29017 |
| 1983 | 4.49165 |
| 1982 | 4.60926 |
| 1981 | 4.65632 |
| 1980 | 4.65933 |
| 1979 | 4.6372 |
| 1978 | 4.59877 |
| 1977 | 4.55231 |
| 1976 | 4.50819 |
| 1975 | 4.46879 |
| 1974 | 4.43185 |
| 1973 | 4.40271 |
| 1972 | 4.3841 |
| 1971 | 4.37017 |
| 1970 | 4.3578 |
| 1969 | 4.34853 |
| 1968 | 4.34222 |
| 1967 | 4.3402 |
| 1966 | 4.3484 |
| 1965 | 4.36971 |
| 1964 | 4.4031 |
| 1963 | 4.44828 |
| 1962 | 4.50233 |
| 1961 | 4.55739 |
| 1960 | 4.60859 |