Year | Value | 2022 | 49.432796724227 | 2021 | 49.424139247892 | 2020 | 49.418569561361 | 2019 | 49.412918668518 | 2018 | 49.401994481147 | 2017 | 49.390085720725 | 2016 | 49.380948033468 | 2015 | 49.37508108951 | 2014 | 49.369435771851 | 2013 | 49.361337035994 | 2012 | 49.354115989176 | 2011 | 49.362009354837 | 2010 | 49.370176157764 | 2009 | 49.362120218761 | 2008 | 49.351532104269 | 2007 | 49.341698253641 | 2006 | 49.332702217434 | 2005 | 49.324450324634 | 2004 | 49.322563133892 | 2003 | 49.328053346588 | 2002 | 49.341380908041 | 2001 | 49.356227770947 | 2000 | 49.367238580859 | 1999 | 49.382465243156 | 1998 | 49.402652551951 | 1997 | 49.423689334022 | 1996 | 49.444385851365 | 1995 | 49.462882020122 | 1994 | 49.482730197173 | 1993 | 49.507133989984 | 1992 | 49.531248504938 | 1991 | 49.551149346765 | 1990 | 49.574855242444 | 1989 | 49.607698031212 | 1988 | 49.639770537816 | 1987 | 49.668103477886 | 1986 | 49.692323551313 | 1985 | 49.716977887232 | 1984 | 49.746455385 | 1983 | 49.777361477723 | 1982 | 49.803423389712 | 1981 | 49.822636397901 | 1980 | 49.837775217084 | 1979 | 49.844142226094 | 1978 | 49.840076046556 | 1977 | 49.831117631223 | 1976 | 49.808169426506 | 1975 | 49.774768060231 | 1974 | 49.742997524886 | 1973 | 49.706789534788 | 1972 | 49.669863846534 | 1971 | 49.634186597474 | 1970 | 49.602630511093 | 1969 | 49.578924904448 | 1968 | 49.561520473546 | 1967 | 49.548793100458 | 1966 | 49.539131396408 | 1965 | 49.538719785204 | 1964 | 49.544131599371 | 1963 | 49.549646829563 | 1962 | 49.555155688488 | 1961 | 49.559254410438 | 1960 | 49.558643568723 |
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