Year | Value | 2021 | 58.221 | 2020 | 58.693 | 2019 | 59.05 | 2018 | 58.916 | 2017 | 58.505 | 2016 | 58.332 | 2015 | 58.058 | 2014 | 57.962 | 2013 | 57.696 | 2012 | 57.627 | 2011 | 57.163 | 2010 | 57.014 | 2009 | 56.568 | 2008 | 56.462 | 2007 | 56.379 | 2006 | 56.033 | 2005 | 55.703 | 2004 | 55.552 | 2003 | 55.263 | 2002 | 55.158 | 2001 | 54.924 | 2000 | 54.684 | 1999 | 54.654 | 1998 | 54.357 | 1997 | 54.304 | 1996 | 53.962 | 1995 | 53.393 | 1994 | 52.711 | 1993 | 52.123 | 1992 | 51.431 | 1991 | 50.894 | 1990 | 50.592 | 1989 | 50.006 | 1988 | 49.643 | 1987 | 48.812 | 1986 | 48.29 | 1985 | 47.602 | 1984 | 46.874 | 1983 | 46.643 | 1982 | 46.351 | 1981 | 45.952 | 1980 | 45.585 | 1979 | 45.169 | 1978 | 44.974 | 1977 | 44.502 | 1976 | 44.027 | 1975 | 43.312 | 1974 | 42.858 | 1973 | 42.406 | 1972 | 42.05 | 1971 | 41.495 | 1970 | 41.184 | 1969 | 40.88 | 1968 | 40.44 | 1967 | 40.055 | 1966 | 39.666 | 1965 | 39.27 | 1964 | 38.914 | 1963 | 38.429 | 1962 | 38.111 | 1961 | 37.73 | 1960 | 37.377 |
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