| 年份 | 博茨瓦纳 |
|---|---|
| 2023 | - |
| 2022 | 6.8755 |
| 2021 | 6.69355 |
| 2020 | 6.48491 |
| 2019 | 6.26068 |
| 2018 | 6.03067 |
| 2017 | 5.79813 |
| 2016 | 5.57639 |
| 2015 | 5.38782 |
| 2014 | 5.2433 |
| 2013 | 5.14272 |
| 2012 | 5.08326 |
| 2011 | 5.05264 |
| 2010 | 5.03716 |
| 2009 | 5.02669 |
| 2008 | 5.01297 |
| 2007 | 4.99208 |
| 2006 | 4.96552 |
| 2005 | 4.93394 |
| 2004 | 4.8989 |
| 2003 | 4.86295 |
| 2002 | 4.82604 |
| 2001 | 4.7678 |
| 2000 | 4.67789 |
| 1999 | 4.56953 |
| 1998 | 4.44766 |
| 1997 | 4.31664 |
| 1996 | 4.18615 |
| 1995 | 4.06677 |
| 1994 | 3.95646 |
| 1993 | 3.81008 |
| 1992 | 3.63055 |
| 1991 | 3.48889 |
| 1990 | 3.38544 |
| 1989 | 3.30034 |
| 1988 | 3.29115 |
| 1987 | 3.35534 |
| 1986 | 3.42972 |
| 1985 | 3.50921 |
| 1984 | 3.59464 |
| 1983 | 3.68618 |
| 1982 | 3.78299 |
| 1981 | 3.86669 |
| 1980 | 3.92897 |
| 1979 | 3.98175 |
| 1978 | 4.02578 |
| 1977 | 4.05794 |
| 1976 | 4.07593 |
| 1975 | 4.0786 |
| 1974 | 4.05972 |
| 1973 | 4.00993 |
| 1972 | 3.94614 |
| 1971 | 3.91116 |
| 1970 | 3.93738 |
| 1969 | 4.02247 |
| 1968 | 4.16286 |
| 1967 | 4.33356 |
| 1966 | 4.47328 |
| 1965 | 4.54189 |
| 1964 | 4.53995 |
| 1963 | 4.46746 |
| 1962 | 4.33435 |
| 1961 | 4.18472 |
| 1960 | 4.05123 |