| 年份 | 尼日尔 |
|---|---|
| 2023 | - |
| 2022 | 1.57397 |
| 2021 | 1.58209 |
| 2020 | 1.58995 |
| 2019 | 1.59406 |
| 2018 | 1.59477 |
| 2017 | 1.5956 |
| 2016 | 1.59599 |
| 2015 | 1.59529 |
| 2014 | 1.5891 |
| 2013 | 1.58151 |
| 2012 | 1.59095 |
| 2011 | 1.62049 |
| 2010 | 1.65992 |
| 2009 | 1.71052 |
| 2008 | 1.76461 |
| 2007 | 1.79656 |
| 2006 | 1.80237 |
| 2005 | 1.79631 |
| 2004 | 1.7848 |
| 2003 | 1.77172 |
| 2002 | 1.75894 |
| 2001 | 1.74679 |
| 2000 | 1.73506 |
| 1999 | 1.72345 |
| 1998 | 1.71281 |
| 1997 | 1.70331 |
| 1996 | 1.69422 |
| 1995 | 1.68562 |
| 1994 | 1.6765 |
| 1993 | 1.66558 |
| 1992 | 1.65385 |
| 1991 | 1.64366 |
| 1990 | 1.63638 |
| 1989 | 1.63162 |
| 1988 | 1.62952 |
| 1987 | 1.63039 |
| 1986 | 1.63293 |
| 1985 | 1.63612 |
| 1984 | 1.64017 |
| 1983 | 1.64459 |
| 1982 | 1.6485 |
| 1981 | 1.65147 |
| 1980 | 1.6527 |
| 1979 | 1.65141 |
| 1978 | 1.64689 |
| 1977 | 1.6393 |
| 1976 | 1.6298 |
| 1975 | 1.61891 |
| 1974 | 1.60726 |
| 1973 | 1.59601 |
| 1972 | 1.58446 |
| 1971 | 1.57049 |
| 1970 | 1.55254 |
| 1969 | 1.53027 |
| 1968 | 1.50235 |
| 1967 | 1.4723 |
| 1966 | 1.44936 |
| 1965 | 1.43803 |
| 1964 | 1.43856 |
| 1963 | 1.45414 |
| 1962 | 1.48043 |
| 1961 | 1.50178 |
| 1960 | 1.50878 |