| 年份 | 乍得 |
|---|---|
| 2023 | - |
| 2022 | 13.3171 |
| 2021 | 13.2874 |
| 2020 | 13.2567 |
| 2019 | 13.2122 |
| 2018 | 13.1489 |
| 2017 | 13.0647 |
| 2016 | 12.9807 |
| 2015 | 12.8923 |
| 2014 | 12.8288 |
| 2013 | 12.8605 |
| 2012 | 12.9235 |
| 2011 | 12.9737 |
| 2010 | 12.981 |
| 2009 | 12.9313 |
| 2008 | 12.9222 |
| 2007 | 12.9364 |
| 2006 | 12.8831 |
| 2005 | 12.8509 |
| 2004 | 12.9234 |
| 2003 | 12.9625 |
| 2002 | 12.8582 |
| 2001 | 12.7009 |
| 2000 | 12.536 |
| 1999 | 12.4215 |
| 1998 | 12.3797 |
| 1997 | 12.2754 |
| 1996 | 12.142 |
| 1995 | 12.2109 |
| 1994 | 12.2901 |
| 1993 | 12.1305 |
| 1992 | 12.1512 |
| 1991 | 12.5272 |
| 1990 | 12.7895 |
| 1989 | 12.8896 |
| 1988 | 13.073 |
| 1987 | 13.2304 |
| 1986 | 13.3209 |
| 1985 | 13.2782 |
| 1984 | 12.9865 |
| 1983 | 12.71 |
| 1982 | 12.7795 |
| 1981 | 12.8309 |
| 1980 | 12.4598 |
| 1979 | 12.1479 |
| 1978 | 12.0584 |
| 1977 | 11.9663 |
| 1976 | 11.8988 |
| 1975 | 11.8596 |
| 1974 | 11.8469 |
| 1973 | 11.8536 |
| 1972 | 11.8661 |
| 1971 | 11.8638 |
| 1970 | 11.8466 |
| 1969 | 11.8228 |
| 1968 | 11.7905 |
| 1967 | 11.7511 |
| 1966 | 11.7074 |
| 1965 | 11.6698 |
| 1964 | 11.484 |
| 1963 | 11.2152 |
| 1962 | 11.0277 |
| 1961 | 10.8559 |
| 1960 | 10.6956 |