| 年份 | 尼日尔 |
|---|---|
| 2023 | - |
| 2022 | 3.71299 |
| 2021 | 3.70742 |
| 2020 | 3.7271 |
| 2019 | 3.76544 |
| 2018 | 3.7876 |
| 2017 | 3.82693 |
| 2016 | 3.86709 |
| 2015 | 3.82886 |
| 2014 | 3.78118 |
| 2013 | 3.81821 |
| 2012 | 3.81058 |
| 2011 | 3.74672 |
| 2010 | 3.7307 |
| 2009 | 3.70117 |
| 2008 | 3.67254 |
| 2007 | 3.64121 |
| 2006 | 3.61443 |
| 2005 | 3.58818 |
| 2004 | 3.54918 |
| 2003 | 3.50446 |
| 2002 | 3.47215 |
| 2001 | 3.45653 |
| 2000 | 3.42375 |
| 1999 | 3.41011 |
| 1998 | 3.37956 |
| 1997 | 3.33553 |
| 1996 | 3.36659 |
| 1995 | 3.32128 |
| 1994 | 3.2138 |
| 1993 | 3.1541 |
| 1992 | 3.11278 |
| 1991 | 3.10507 |
| 1990 | 3.08846 |
| 1989 | 3.05025 |
| 1988 | 3.03929 |
| 1987 | 3.03417 |
| 1986 | 3.02498 |
| 1985 | 3.01925 |
| 1984 | 3.01677 |
| 1983 | 3.03317 |
| 1982 | 3.06555 |
| 1981 | 3.07989 |
| 1980 | 3.05979 |
| 1979 | 2.99747 |
| 1978 | 2.89234 |
| 1977 | 2.80338 |
| 1976 | 2.75523 |
| 1975 | 2.71309 |
| 1974 | 2.67562 |
| 1973 | 2.66525 |
| 1972 | 2.6587 |
| 1971 | 2.69084 |
| 1970 | 2.75105 |
| 1969 | 2.79094 |
| 1968 | 2.83921 |
| 1967 | 2.8769 |
| 1966 | 2.8929 |
| 1965 | 2.91656 |
| 1964 | 2.94649 |
| 1963 | 2.96365 |
| 1962 | 2.96833 |
| 1961 | 2.96077 |
| 1960 | - |