Year | Value | 2021 | 10.065 | 2020 | 8.964 | 2019 | 7.539 | 2018 | 7.496 | 2017 | 7.579 | 2016 | 7.529 | 2015 | 7.46 | 2014 | 7.43 | 2013 | 7.457 | 2012 | 7.494 | 2011 | 7.456 | 2010 | 7.406 | 2009 | 7.386 | 2008 | 7.41 | 2007 | 7.314 | 2006 | 7.323 | 2005 | 7.336 | 2004 | 7.995 | 2003 | 7.223 | 2002 | 7.248 | 2001 | 7.329 | 2000 | 7.383 | 1999 | 7.39 | 1998 | 7.431 | 1997 | 7.458 | 1996 | 7.541 | 1995 | 7.505 | 1994 | 7.596 | 1993 | 7.636 | 1992 | 7.786 | 1991 | 8.007 | 1990 | 8.111 | 1989 | 8.31 | 1988 | 8.507 | 1987 | 8.591 | 1986 | 8.706 | 1985 | 8.937 | 1984 | 9.256 | 1983 | 9.495 | 1982 | 9.757 | 1981 | 10.061 | 1980 | 10.264 | 1979 | 10.573 | 1978 | 10.871 | 1977 | 11.131 | 1976 | 11.45 | 1975 | 11.771 | 1974 | 12.094 | 1973 | 12.465 | 1972 | 12.844 | 1971 | 13.273 | 1970 | 13.677 | 1969 | 14.112 | 1968 | 14.604 | 1967 | 15.015 | 1966 | 16.791 | 1965 | 20.958 | 1964 | 16.31 | 1963 | 16.824 | 1962 | 17.18 | 1961 | 17.641 | 1960 | 18.024 |
|