| 年份 | 博茨瓦纳 |
|---|---|
| 2023 | - |
| 2022 | 6.73314 |
| 2021 | 6.55758 |
| 2020 | 6.36198 |
| 2019 | 6.15361 |
| 2018 | 5.94087 |
| 2017 | 5.72409 |
| 2016 | 5.51245 |
| 2015 | 5.32279 |
| 2014 | 5.1661 |
| 2013 | 5.04227 |
| 2012 | 4.94845 |
| 2011 | 4.87757 |
| 2010 | 4.82069 |
| 2009 | 4.77132 |
| 2008 | 4.72062 |
| 2007 | 4.66525 |
| 2006 | 4.61225 |
| 2005 | 4.56936 |
| 2004 | 4.53684 |
| 2003 | 4.51313 |
| 2002 | 4.49969 |
| 2001 | 4.45965 |
| 2000 | 4.37829 |
| 1999 | 4.27944 |
| 1998 | 4.16804 |
| 1997 | 4.04834 |
| 1996 | 3.92942 |
| 1995 | 3.82406 |
| 1994 | 3.73059 |
| 1993 | 3.59683 |
| 1992 | 3.4302 |
| 1991 | 3.29832 |
| 1990 | 3.19753 |
| 1989 | 3.11592 |
| 1988 | 3.11165 |
| 1987 | 3.1812 |
| 1986 | 3.25945 |
| 1985 | 3.34392 |
| 1984 | 3.43788 |
| 1983 | 3.54227 |
| 1982 | 3.65282 |
| 1981 | 3.74226 |
| 1980 | 3.79198 |
| 1979 | 3.81738 |
| 1978 | 3.83068 |
| 1977 | 3.83171 |
| 1976 | 3.81962 |
| 1975 | 3.79494 |
| 1974 | 3.75018 |
| 1973 | 3.67402 |
| 1972 | 3.60075 |
| 1971 | 3.60801 |
| 1970 | 3.70407 |
| 1969 | 3.84538 |
| 1968 | 4.03055 |
| 1967 | 4.2353 |
| 1966 | 4.39356 |
| 1965 | 4.46088 |
| 1964 | 4.46031 |
| 1963 | 4.39753 |
| 1962 | 4.26695 |
| 1961 | 4.12318 |
| 1960 | 4.0065 |