| 年份 | 博茨瓦纳 |
|---|---|
| 2023 | - |
| 2022 | 0.362217 |
| 2021 | 0.371556 |
| 2020 | 0.385412 |
| 2019 | 0.385744 |
| 2018 | 0.382898 |
| 2017 | 0.380184 |
| 2016 | 0.377529 |
| 2015 | 0.37478 |
| 2014 | 0.371768 |
| 2013 | 0.368258 |
| 2012 | 0.364625 |
| 2011 | 0.361667 |
| 2010 | 0.360197 |
| 2009 | 0.360255 |
| 2008 | 0.361471 |
| 2007 | 0.362856 |
| 2006 | 0.362213 |
| 2005 | 0.357987 |
| 2004 | 0.350349 |
| 2003 | 0.339033 |
| 2002 | 0.324433 |
| 2001 | 0.309347 |
| 2000 | 0.295785 |
| 1999 | 0.283287 |
| 1998 | 0.271338 |
| 1997 | 0.26048 |
| 1996 | 0.250381 |
| 1995 | 0.240684 |
| 1994 | 0.232204 |
| 1993 | 0.225793 |
| 1992 | 0.221677 |
| 1991 | 0.218776 |
| 1990 | 0.216787 |
| 1989 | 0.216649 |
| 1988 | 0.219006 |
| 1987 | 0.223924 |
| 1986 | 0.230041 |
| 1985 | 0.235176 |
| 1984 | 0.237899 |
| 1983 | 0.238221 |
| 1982 | 0.236414 |
| 1981 | 0.235915 |
| 1980 | 0.240196 |
| 1979 | 0.248577 |
| 1978 | 0.261855 |
| 1977 | 0.280582 |
| 1976 | 0.301814 |
| 1975 | 0.322827 |
| 1974 | 0.342239 |
| 1973 | 0.359265 |
| 1972 | 0.373566 |
| 1971 | 0.381365 |
| 1970 | 0.38069 |
| 1969 | 0.374301 |
| 1968 | 0.364984 |
| 1967 | 0.355037 |
| 1966 | 0.344897 |
| 1965 | 0.335184 |
| 1964 | 0.329426 |
| 1963 | 0.327538 |
| 1962 | 0.325749 |
| 1961 | 0.323872 |
| 1960 | 0.320333 |