Year | Value | 2021 | 59.728 | 2020 | 60.071 | 2019 | 60.695 | 2018 | 60.59 | 2017 | 60.354 | 2016 | 59.939 | 2015 | 59.695 | 2014 | 59.285 | 2013 | 59.266 | 2012 | 58.687 | 2011 | 58.507 | 2010 | 58.303 | 2009 | 57.91 | 2008 | 57.514 | 2007 | 57.084 | 2006 | 57.041 | 2005 | 56.492 | 2004 | 56.275 | 2003 | 56.005 | 2002 | 55.759 | 2001 | 55.379 | 2000 | 55.111 | 1999 | 54.759 | 1998 | 54.681 | 1997 | 54.267 | 1996 | 54.459 | 1995 | 54.542 | 1994 | 53.651 | 1993 | 53.868 | 1992 | 51.244 | 1991 | 52.703 | 1990 | 53.524 | 1989 | 53.437 | 1988 | 53.298 | 1987 | 52.935 | 1986 | 52.519 | 1985 | 52.196 | 1984 | 51.789 | 1983 | 51.313 | 1982 | 50.902 | 1981 | 50.29 | 1980 | 49.998 | 1979 | 49.534 | 1978 | 49.06 | 1977 | 48.593 | 1976 | 48.131 | 1975 | 47.97 | 1974 | 47.534 | 1973 | 47.117 | 1972 | 46.593 | 1971 | 45.513 | 1970 | 45.636 | 1969 | 45.047 | 1968 | 44.512 | 1967 | 43.92 | 1966 | 43.55 | 1965 | 43.194 | 1964 | 42.77 | 1963 | 42.447 | 1962 | 42.149 | 1961 | 41.827 | 1960 | 41.625 |
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