Year | Value | 2021 | 45.293 | 2020 | 45.588 | 2019 | 45.859 | 2018 | 46.127 | 2017 | 46.351 | 2016 | 46.52 | 2015 | 46.558 | 2014 | 46.752 | 2013 | 47.123 | 2012 | 47.398 | 2011 | 47.99 | 2010 | 48.51 | 2009 | 48.882 | 2008 | 49.297 | 2007 | 49.694 | 2006 | 50.096 | 2005 | 50.63 | 2004 | 51.058 | 2003 | 51.456 | 2002 | 51.841 | 2001 | 52.219 | 2000 | 52.659 | 1999 | 52.957 | 1998 | 53.399 | 1997 | 53.659 | 1996 | 53.93 | 1995 | 54.068 | 1994 | 53.953 | 1993 | 54.254 | 1992 | 54.492 | 1991 | 54.816 | 1990 | 55.165 | 1989 | 55.225 | 1988 | 55.618 | 1987 | 56.212 | 1986 | 56.363 | 1985 | 56.895 | 1984 | 57.126 | 1983 | 56.9 | 1982 | 57.081 | 1981 | 57.251 | 1980 | 57.072 | 1979 | 56.68 | 1978 | 56.237 | 1977 | 55.722 | 1976 | 55.645 | 1975 | 55.651 | 1974 | 55.627 | 1973 | 55.579 | 1972 | 55.564 | 1971 | 55.659 | 1970 | 55.718 | 1969 | 55.808 | 1968 | 55.995 | 1967 | 56.322 | 1966 | 56.581 | 1965 | 56.784 | 1964 | 57.192 | 1963 | 57.45 | 1962 | 57.683 | 1961 | 57.903 | 1960 | 58.121 |
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