| 年份 | 博茨瓦纳 |
|---|---|
| 2023 | - |
| 2022 | - |
| 2021 | 31.1 |
| 2020 | 31.9 |
| 2019 | 32.8 |
| 2018 | 34 |
| 2017 | 35.4 |
| 2016 | 38.6 |
| 2015 | 40 |
| 2014 | 42.2 |
| 2013 | 43.3 |
| 2012 | 46.8 |
| 2011 | 52.1 |
| 2010 | 52.5 |
| 2009 | 52.9 |
| 2008 | 53.6 |
| 2007 | 51.5 |
| 2006 | 47.3 |
| 2005 | 44.9 |
| 2004 | 44.7 |
| 2003 | 41.8 |
| 2002 | 39.3 |
| 2001 | 38 |
| 2000 | 38.4 |
| 1999 | 39.6 |
| 1998 | 40.1 |
| 1997 | 40.5 |
| 1996 | 40.2 |
| 1995 | 41.3 |
| 1994 | 39.7 |
| 1993 | 38.7 |
| 1992 | 37.8 |
| 1991 | 37.3 |
| 1990 | 37.5 |
| 1989 | 38.6 |
| 1988 | 40.6 |
| 1987 | 43.1 |
| 1986 | 45.8 |
| 1985 | 48.4 |
| 1984 | 50.7 |
| 1983 | 53 |
| 1982 | 55.3 |
| 1981 | 57.9 |
| 1980 | 60.6 |
| 1979 | 63.6 |
| 1978 | 67 |
| 1977 | 70.7 |
| 1976 | 74.6 |
| 1975 | 78.6 |
| 1974 | 82.4 |
| 1973 | 85.6 |
| 1972 | 88.6 |
| 1971 | 91.6 |
| 1970 | 94.8 |
| 1969 | 97.9 |
| 1968 | 100.8 |
| 1967 | 103.6 |
| 1966 | 106 |
| 1965 | 108.4 |
| 1964 | 110.8 |
| 1963 | 113.3 |
| 1962 | 116 |
| 1961 | 119 |
| 1960 | 122.4 |