| 年份 | 乍得 |
|---|---|
| 2023 | - |
| 2022 | 1.301 |
| 2021 | 1.29105 |
| 2020 | 1.28205 |
| 2019 | 1.27083 |
| 2018 | 1.25823 |
| 2017 | 1.24784 |
| 2016 | 1.23971 |
| 2015 | 1.23461 |
| 2014 | 1.21521 |
| 2013 | 1.18757 |
| 2012 | 1.17004 |
| 2011 | 1.1559 |
| 2010 | 1.14488 |
| 2009 | 1.16033 |
| 2008 | 1.1919 |
| 2007 | 1.21321 |
| 2006 | 1.23385 |
| 2005 | 1.254 |
| 2004 | 1.27644 |
| 2003 | 1.30273 |
| 2002 | 1.33204 |
| 2001 | 1.36244 |
| 2000 | 1.3922 |
| 1999 | 1.42052 |
| 1998 | 1.44671 |
| 1997 | 1.47104 |
| 1996 | 1.49684 |
| 1995 | 1.52885 |
| 1994 | 1.5634 |
| 1993 | 1.59284 |
| 1992 | 1.62466 |
| 1991 | 1.66551 |
| 1990 | 1.70527 |
| 1989 | 1.74108 |
| 1988 | 1.77958 |
| 1987 | 1.81952 |
| 1986 | 1.85962 |
| 1985 | 1.89428 |
| 1984 | 1.91525 |
| 1983 | 1.93864 |
| 1982 | 1.98867 |
| 1981 | 2.03464 |
| 1980 | 2.03833 |
| 1979 | 2.039 |
| 1978 | 2.05154 |
| 1977 | 2.05849 |
| 1976 | 2.06535 |
| 1975 | 2.07449 |
| 1974 | 2.08592 |
| 1973 | 2.09917 |
| 1972 | 2.11493 |
| 1971 | 2.13212 |
| 1970 | 2.14961 |
| 1969 | 2.16806 |
| 1968 | 2.18848 |
| 1967 | 2.21063 |
| 1966 | 2.2322 |
| 1965 | 2.25153 |
| 1964 | 2.26913 |
| 1963 | 2.28592 |
| 1962 | 2.29997 |
| 1961 | 2.30803 |
| 1960 | 2.30821 |