| 年份 | 尼日尔 |
|---|---|
| 2023 | - |
| 2022 | 1.95433 |
| 2021 | 1.97442 |
| 2020 | 1.99295 |
| 2019 | 2.00588 |
| 2018 | 2.01278 |
| 2017 | 2.01787 |
| 2016 | 2.02148 |
| 2015 | 2.02404 |
| 2014 | 2.02578 |
| 2013 | 2.02721 |
| 2012 | 2.02887 |
| 2011 | 2.03019 |
| 2010 | 2.03028 |
| 2009 | 1.97592 |
| 2008 | 1.87702 |
| 2007 | 1.80075 |
| 2006 | 1.74285 |
| 2005 | 1.69542 |
| 2004 | 1.72214 |
| 2003 | 1.80554 |
| 2002 | 1.85392 |
| 2001 | 1.87209 |
| 2000 | 1.87143 |
| 1999 | 1.86047 |
| 1998 | 1.8432 |
| 1997 | 1.823 |
| 1996 | 1.80368 |
| 1995 | 1.78556 |
| 1994 | 1.76708 |
| 1993 | 1.7506 |
| 1992 | 1.73766 |
| 1991 | 1.72579 |
| 1990 | 1.71364 |
| 1989 | 1.70162 |
| 1988 | 1.68974 |
| 1987 | 1.67895 |
| 1986 | 1.67173 |
| 1985 | 1.66983 |
| 1984 | 1.67299 |
| 1983 | 1.68026 |
| 1982 | 1.69064 |
| 1981 | 1.70147 |
| 1980 | 1.7104 |
| 1979 | 1.7172 |
| 1978 | 1.7215 |
| 1977 | 1.72329 |
| 1976 | 1.72455 |
| 1975 | 1.72675 |
| 1974 | 1.72965 |
| 1973 | 1.73301 |
| 1972 | 1.73669 |
| 1971 | 1.74003 |
| 1970 | 1.74215 |
| 1969 | 1.7426 |
| 1968 | 1.74132 |
| 1967 | 1.73873 |
| 1966 | 1.73633 |
| 1965 | 1.73455 |
| 1964 | 1.73324 |
| 1963 | 1.73335 |
| 1962 | 1.73186 |
| 1961 | 1.72021 |
| 1960 | 1.69274 |