| 年份 | 乍得 |
|---|---|
| 2023 | - |
| 2022 | 2.00829 |
| 2021 | 2.02032 |
| 2020 | 2.03264 |
| 2019 | 2.03497 |
| 2018 | 2.02978 |
| 2017 | 2.02714 |
| 2016 | 2.02761 |
| 2015 | 2.03206 |
| 2014 | 2.06063 |
| 2013 | 2.10448 |
| 2012 | 2.14381 |
| 2011 | 2.1858 |
| 2010 | 2.23031 |
| 2009 | 2.27877 |
| 2008 | 2.3303 |
| 2007 | 2.38523 |
| 2006 | 2.44417 |
| 2005 | 2.50638 |
| 2004 | 2.56903 |
| 2003 | 2.62916 |
| 2002 | 2.68688 |
| 2001 | 2.74489 |
| 2000 | 2.80509 |
| 1999 | 2.8676 |
| 1998 | 2.93156 |
| 1997 | 2.99515 |
| 1996 | 3.05963 |
| 1995 | 3.13015 |
| 1994 | 3.19863 |
| 1993 | 3.25294 |
| 1992 | 3.30961 |
| 1991 | 3.37808 |
| 1990 | 3.43525 |
| 1989 | 3.4802 |
| 1988 | 3.52776 |
| 1987 | 3.57228 |
| 1986 | 3.61097 |
| 1985 | 3.6362 |
| 1984 | 3.63893 |
| 1983 | 3.65011 |
| 1982 | 3.70141 |
| 1981 | 3.74144 |
| 1980 | 3.72026 |
| 1979 | 3.70658 |
| 1978 | 3.72357 |
| 1977 | 3.73849 |
| 1976 | 3.75565 |
| 1975 | 3.77753 |
| 1974 | 3.80358 |
| 1973 | 3.83012 |
| 1972 | 3.85566 |
| 1971 | 3.87924 |
| 1970 | 3.8992 |
| 1969 | 3.91588 |
| 1968 | 3.93161 |
| 1967 | 3.9469 |
| 1966 | 3.96041 |
| 1965 | 3.97164 |
| 1964 | 3.9783 |
| 1963 | 3.97829 |
| 1962 | 3.97673 |
| 1961 | 3.98087 |
| 1960 | 3.99643 |