Year | Value | 2021 | 10.709 | 2020 | 8.475 | 2019 | 8.248 | 2018 | 8.403 | 2017 | 8.47 | 2016 | 8.686 | 2015 | 9.077 | 2014 | 9.427 | 2013 | 9.91 | 2012 | 10.372 | 2011 | 10.861 | 2010 | 11.062 | 2009 | 11.249 | 2008 | 11.61 | 2007 | 12.046 | 2006 | 12.537 | 2005 | 12.954 | 2004 | 13.199 | 2003 | 13.241 | 2002 | 13.12 | 2001 | 13.129 | 2000 | 12.718 | 1999 | 12.142 | 1998 | 11.569 | 1997 | 10.837 | 1996 | 10.22 | 1995 | 9.524 | 1994 | 9.089 | 1993 | 8.757 | 1992 | 8.568 | 1991 | 8.425 | 1990 | 8.31 | 1989 | 8.387 | 1988 | 9.399 | 1987 | 9.478 | 1986 | 9.815 | 1985 | 10.113 | 1984 | 10.433 | 1983 | 10.76 | 1982 | 11.023 | 1981 | 11.368 | 1980 | 11.63 | 1979 | 11.093 | 1978 | 11.333 | 1977 | 11.689 | 1976 | 12.043 | 1975 | 12.372 | 1974 | 12.786 | 1973 | 13.129 | 1972 | 13.513 | 1971 | 13.875 | 1970 | 14.272 | 1969 | 14.627 | 1968 | 14.975 | 1967 | 15.354 | 1966 | 15.749 | 1965 | 16.047 | 1964 | 16.447 | 1963 | 16.913 | 1962 | 17.321 | 1961 | 17.782 | 1960 | 18.247 |
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