Year | Value | 2021 | 54.283 | 2020 | 54.396 | 2019 | 54.908 | 2018 | 54.317 | 2017 | 53.752 | 2016 | 53.317 | 2015 | 53.132 | 2014 | 52.63 | 2013 | 52.16 | 2012 | 51.849 | 2011 | 51.279 | 2010 | 50.798 | 2009 | 50.361 | 2008 | 50.281 | 2007 | 50.005 | 2006 | 49.515 | 2005 | 49.304 | 2004 | 49.313 | 2003 | 49.102 | 2002 | 48.875 | 2001 | 48.802 | 2000 | 48.557 | 1999 | 48.335 | 1998 | 48.234 | 1997 | 48.187 | 1996 | 48.041 | 1995 | 47.713 | 1994 | 47.514 | 1993 | 47.438 | 1992 | 47.5 | 1991 | 47.438 | 1990 | 47.793 | 1989 | 47.738 | 1988 | 47.494 | 1987 | 47.422 | 1986 | 47.538 | 1985 | 47.121 | 1984 | 47.001 | 1983 | 46.755 | 1982 | 46.059 | 1981 | 45.596 | 1980 | 45.143 | 1979 | 44.873 | 1978 | 44.529 | 1977 | 44.334 | 1976 | 44.113 | 1975 | 43.464 | 1974 | 43.429 | 1973 | 43.536 | 1972 | 43.638 | 1971 | 42.256 | 1970 | 42.749 | 1969 | 42.354 | 1968 | 41.947 | 1967 | 41.605 | 1966 | 41.271 | 1965 | 40.716 | 1964 | 40.908 | 1963 | 40.618 | 1962 | 40.312 | 1961 | 40.196 | 1960 | 39.971 |
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