| 年份 | 博茨瓦纳 |
|---|---|
| 2023 | - |
| 2022 | - |
| 2021 | 28.3 |
| 2020 | 29 |
| 2019 | 29.9 |
| 2018 | 30.9 |
| 2017 | 32.3 |
| 2016 | 35.3 |
| 2015 | 36.6 |
| 2014 | 38.7 |
| 2013 | 39.7 |
| 2012 | 42.9 |
| 2011 | 48 |
| 2010 | 48.3 |
| 2009 | 48.7 |
| 2008 | 49.4 |
| 2007 | 47.3 |
| 2006 | 43.5 |
| 2005 | 41.4 |
| 2004 | 41.1 |
| 2003 | 38.4 |
| 2002 | 36 |
| 2001 | 34.7 |
| 2000 | 35.1 |
| 1999 | 36.1 |
| 1998 | 36.6 |
| 1997 | 36.9 |
| 1996 | 36.6 |
| 1995 | 37.5 |
| 1994 | 36.1 |
| 1993 | 35.1 |
| 1992 | 34.2 |
| 1991 | 33.8 |
| 1990 | 33.8 |
| 1989 | 34.8 |
| 1988 | 36.6 |
| 1987 | 38.9 |
| 1986 | 41.4 |
| 1985 | 43.7 |
| 1984 | 45.8 |
| 1983 | 48 |
| 1982 | 50.1 |
| 1981 | 52.4 |
| 1980 | 54.9 |
| 1979 | 57.7 |
| 1978 | 60.9 |
| 1977 | 64.3 |
| 1976 | 68.1 |
| 1975 | 71.9 |
| 1974 | 75.3 |
| 1973 | 78.4 |
| 1972 | 81.2 |
| 1971 | 84.1 |
| 1970 | 87 |
| 1969 | 90 |
| 1968 | 92.7 |
| 1967 | 95.4 |
| 1966 | 97.8 |
| 1965 | 100 |
| 1964 | 102.2 |
| 1963 | 104.7 |
| 1962 | 107.4 |
| 1961 | 110.3 |
| 1960 | 113.6 |