| 年份 | 乍得 |
|---|---|
| 2023 | - |
| 2022 | 0.276006 |
| 2021 | 0.284211 |
| 2020 | 0.291483 |
| 2019 | 0.29648 |
| 2018 | 0.30031 |
| 2017 | 0.304937 |
| 2016 | 0.310103 |
| 2015 | 0.315785 |
| 2014 | 0.321665 |
| 2013 | 0.326786 |
| 2012 | 0.331608 |
| 2011 | 0.336973 |
| 2010 | 0.343387 |
| 2009 | 0.350736 |
| 2008 | 0.358688 |
| 2007 | 0.367283 |
| 2006 | 0.37631 |
| 2005 | 0.385614 |
| 2004 | 0.394854 |
| 2003 | 0.403536 |
| 2002 | 0.411882 |
| 2001 | 0.420422 |
| 2000 | 0.429274 |
| 1999 | 0.438264 |
| 1998 | 0.447413 |
| 1997 | 0.456354 |
| 1996 | 0.464831 |
| 1995 | 0.472827 |
| 1994 | 0.479539 |
| 1993 | 0.48439 |
| 1992 | 0.48882 |
| 1991 | 0.493684 |
| 1990 | 0.497952 |
| 1989 | 0.501457 |
| 1988 | 0.50488 |
| 1987 | 0.509007 |
| 1986 | 0.51286 |
| 1985 | 0.515184 |
| 1984 | 0.517 |
| 1983 | 0.520995 |
| 1982 | 0.528404 |
| 1981 | 0.534011 |
| 1980 | 0.534238 |
| 1979 | 0.535061 |
| 1978 | 0.538036 |
| 1977 | 0.540421 |
| 1976 | 0.54222 |
| 1975 | 0.543025 |
| 1974 | 0.542196 |
| 1973 | 0.53882 |
| 1972 | 0.533733 |
| 1971 | 0.52903 |
| 1970 | 0.52674 |
| 1969 | 0.527668 |
| 1968 | 0.532511 |
| 1967 | 0.541659 |
| 1966 | 0.553189 |
| 1965 | 0.564657 |
| 1964 | 0.575609 |
| 1963 | 0.58694 |
| 1962 | 0.598158 |
| 1961 | 0.608674 |
| 1960 | 0.6183 |