Year | Value | 2021 | 58.758 | 2020 | 58.404 | 2019 | 58.941 | 2018 | 58.419 | 2017 | 57.491 | 2016 | 57.235 | 2015 | 56.151 | 2014 | 55.422 | 2013 | 55.338 | 2012 | 54.55 | 2011 | 53.766 | 2010 | 52.863 | 2009 | 51.852 | 2008 | 50.765 | 2007 | 49.656 | 2006 | 48.739 | 2005 | 47.587 | 2004 | 46.881 | 2003 | 46.181 | 2002 | 45.557 | 2001 | 44.695 | 2000 | 44.097 | 1999 | 39.117 | 1998 | 40.975 | 1997 | 42.569 | 1996 | 42.577 | 1995 | 41.187 | 1994 | 41.588 | 1993 | 42.358 | 1992 | 42.352 | 1991 | 42.297 | 1990 | 42.996 | 1989 | 42.935 | 1988 | 42.901 | 1987 | 42.885 | 1986 | 42.552 | 1985 | 42.595 | 1984 | 42.616 | 1983 | 42.432 | 1982 | 42.178 | 1981 | 41.957 | 1980 | 41.728 | 1979 | 41.463 | 1978 | 41.025 | 1977 | 40.665 | 1976 | 40.256 | 1975 | 39.829 | 1974 | 39.358 | 1973 | 38.904 | 1972 | 38.429 | 1971 | 37.937 | 1970 | 37.467 | 1969 | 36.835 | 1968 | 36.48 | 1967 | 36.042 | 1966 | 35.445 | 1965 | 34.929 | 1964 | 34.457 | 1963 | 33.949 | 1962 | 33.52 | 1961 | 33.068 | 1960 | 32.682 |
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