Year | Value | 2021 | 73.972 | 2020 | 74.584 | 2019 | 75.437 | 2018 | 75.131 | 2017 | 75.03 | 2016 | 76.598 | 2015 | 76.954 | 2014 | 76.773 | 2013 | 74.917 | 2012 | 74.608 | 2011 | 74.684 | 2010 | 75.132 | 2009 | 75.441 | 2008 | 75.742 | 2007 | 75.417 | 2006 | 75.926 | 2005 | 75.542 | 2004 | 74.24 | 2003 | 74.148 | 2002 | 74.858 | 2001 | 74.522 | 2000 | 74.514 | 1999 | 75.034 | 1998 | 73.48 | 1997 | 73.76 | 1996 | 72.858 | 1995 | 72.406 | 1994 | 72.338 | 1993 | 72.293 | 1992 | 72.509 | 1991 | 71.954 | 1990 | 72.324 | 1989 | 72.481 | 1988 | 72.871 | 1987 | 72.201 | 1986 | 72.202 | 1985 | 72.282 | 1984 | 72.418 | 1983 | 72.585 | 1982 | 72.432 | 1981 | 71.228 | 1980 | 70.918 | 1979 | 71.551 | 1978 | 71.961 | 1977 | 72.269 | 1976 | 72.709 | 1975 | 72.579 | 1974 | 72.309 | 1973 | 72.096 | 1972 | 71.736 | 1971 | 71.437 | 1970 | 71.907 | 1969 | 70.158 | 1968 | 68.795 | 1967 | 69.091 | 1966 | 68.325 | 1965 | 66.403 | 1964 | 68.604 | 1963 | 68.566 | 1962 | 66.807 | 1961 | 65.73 | 1960 | 66.246 |
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