| 年份 | 乍得 |
|---|---|
| 2023 | - |
| 2022 | 0.61248 |
| 2021 | 0.60338 |
| 2020 | 0.594186 |
| 2019 | 0.597488 |
| 2018 | 0.609857 |
| 2017 | 0.617952 |
| 2016 | 0.626263 |
| 2015 | 0.63405 |
| 2014 | 0.643261 |
| 2013 | 0.655627 |
| 2012 | 0.670289 |
| 2011 | 0.686657 |
| 2010 | 0.704329 |
| 2009 | 0.722557 |
| 2008 | 0.741272 |
| 2007 | 0.759905 |
| 2006 | 0.779278 |
| 2005 | 0.800304 |
| 2004 | 0.823177 |
| 2003 | 0.847259 |
| 2002 | 0.869506 |
| 2001 | 0.89025 |
| 2000 | 0.911539 |
| 1999 | 0.934513 |
| 1998 | 0.959181 |
| 1997 | 0.983929 |
| 1996 | 1.00777 |
| 1995 | 1.03597 |
| 1994 | 1.06277 |
| 1993 | 1.07426 |
| 1992 | 1.08389 |
| 1991 | 1.10481 |
| 1990 | 1.12178 |
| 1989 | 1.1326 |
| 1988 | 1.148 |
| 1987 | 1.16408 |
| 1986 | 1.18058 |
| 1985 | 1.19271 |
| 1984 | 1.19043 |
| 1983 | 1.19156 |
| 1982 | 1.2213 |
| 1981 | 1.24864 |
| 1980 | 1.23741 |
| 1979 | 1.22576 |
| 1978 | 1.22629 |
| 1977 | 1.22277 |
| 1976 | 1.22198 |
| 1975 | 1.22838 |
| 1974 | 1.24257 |
| 1973 | 1.26444 |
| 1972 | 1.29018 |
| 1971 | 1.31078 |
| 1970 | 1.319 |
| 1969 | 1.31359 |
| 1968 | 1.29362 |
| 1967 | 1.26307 |
| 1966 | 1.23519 |
| 1965 | 1.22132 |
| 1964 | 1.22199 |
| 1963 | 1.23733 |
| 1962 | 1.26663 |
| 1961 | 1.29824 |
| 1960 | 1.32263 |