| 年份 | 乍得 |
|---|---|
| 2023 | - |
| 2022 | 0.244446 |
| 2021 | 0.253909 |
| 2020 | 0.262857 |
| 2019 | 0.269047 |
| 2018 | 0.272699 |
| 2017 | 0.276122 |
| 2016 | 0.280203 |
| 2015 | 0.285846 |
| 2014 | 0.292213 |
| 2013 | 0.297254 |
| 2012 | 0.302545 |
| 2011 | 0.308538 |
| 2010 | 0.315317 |
| 2009 | 0.32341 |
| 2008 | 0.331398 |
| 2007 | 0.340044 |
| 2006 | 0.349737 |
| 2005 | 0.3596 |
| 2004 | 0.367382 |
| 2003 | 0.371727 |
| 2002 | 0.376362 |
| 2001 | 0.382649 |
| 2000 | 0.389761 |
| 1999 | 0.397224 |
| 1998 | 0.405218 |
| 1997 | 0.413765 |
| 1996 | 0.422679 |
| 1995 | 0.427757 |
| 1994 | 0.431021 |
| 1993 | 0.441535 |
| 1992 | 0.453461 |
| 1991 | 0.458075 |
| 1990 | 0.461259 |
| 1989 | 0.465785 |
| 1988 | 0.467646 |
| 1987 | 0.46691 |
| 1986 | 0.462977 |
| 1985 | 0.458762 |
| 1984 | 0.461372 |
| 1983 | 0.467056 |
| 1982 | 0.461203 |
| 1981 | 0.449848 |
| 1980 | 0.447516 |
| 1979 | 0.445816 |
| 1978 | 0.439586 |
| 1977 | 0.432565 |
| 1976 | 0.426785 |
| 1975 | 0.424679 |
| 1974 | 0.426046 |
| 1973 | 0.430208 |
| 1972 | 0.436755 |
| 1971 | 0.443952 |
| 1970 | 0.449655 |
| 1969 | 0.453234 |
| 1968 | 0.455029 |
| 1967 | 0.455001 |
| 1966 | 0.454516 |
| 1965 | 0.455227 |
| 1964 | 0.455925 |
| 1963 | 0.455384 |
| 1962 | 0.454935 |
| 1961 | 0.45423 |
| 1960 | 0.452898 |