| 年份 | 尼日尔  | 
                                                            
|---|---|
| 2023 | - | 
| 2022 | 2.00182 | 
| 2021 | 2.01967 | 
| 2020 | 2.0359 | 
| 2019 | 2.04774 | 
| 2018 | 2.05516 | 
| 2017 | 2.06123 | 
| 2016 | 2.06619 | 
| 2015 | 2.0705 | 
| 2014 | 2.07389 | 
| 2013 | 2.07667 | 
| 2012 | 2.0798 | 
| 2011 | 2.08232 | 
| 2010 | 2.08284 | 
| 2009 | 2.07649 | 
| 2008 | 2.06855 | 
| 2007 | 2.08272 | 
| 2006 | 2.12314 | 
| 2005 | 2.17671 | 
| 2004 | 2.24411 | 
| 2003 | 2.31521 | 
| 2002 | 2.35695 | 
| 2001 | 2.36417 | 
| 2000 | 2.3554 | 
| 1999 | 2.33872 | 
| 1998 | 2.31915 | 
| 1997 | 2.29926 | 
| 1996 | 2.27995 | 
| 1995 | 2.26138 | 
| 1994 | 2.2427 | 
| 1993 | 2.22459 | 
| 1992 | 2.20812 | 
| 1991 | 2.19266 | 
| 1990 | 2.17795 | 
| 1989 | 2.16361 | 
| 1988 | 2.14862 | 
| 1987 | 2.13406 | 
| 1986 | 2.12288 | 
| 1985 | 2.11689 | 
| 1984 | 2.11552 | 
| 1983 | 2.11777 | 
| 1982 | 2.12347 | 
| 1981 | 2.13116 | 
| 1980 | 2.1392 | 
| 1979 | 2.14733 | 
| 1978 | 2.15535 | 
| 1977 | 2.16192 | 
| 1976 | 2.16609 | 
| 1975 | 2.16737 | 
| 1974 | 2.16602 | 
| 1973 | 2.16224 | 
| 1972 | 2.15612 | 
| 1971 | 2.14875 | 
| 1970 | 2.14056 | 
| 1969 | 2.13103 | 
| 1968 | 2.1205 | 
| 1967 | 2.10849 | 
| 1966 | 2.09246 | 
| 1965 | 2.07083 | 
| 1964 | 2.04365 | 
| 1963 | 2.009 | 
| 1962 | 1.97135 | 
| 1961 | 1.94336 | 
| 1960 | 1.93125 |