Year | Value | 2022 | 50.108451148411 | 2021 | 50.101185883592 | 2020 | 50.0945230551 | 2019 | 50.087487889638 | 2018 | 50.080171412267 | 2017 | 50.071396334645 | 2016 | 50.060402355885 | 2015 | 50.048443061733 | 2014 | 50.034212389619 | 2013 | 50.018299006484 | 2012 | 50.000434552875 | 2011 | 49.979984529031 | 2010 | 49.95772677233 | 2009 | 49.933321000754 | 2008 | 49.906499246412 | 2007 | 49.877078638859 | 2006 | 49.842988728994 | 2005 | 49.806856327641 | 2004 | 49.771972712991 | 2003 | 49.738502276343 | 2002 | 49.705872224988 | 2001 | 49.675917461792 | 2000 | 49.647638221693 | 1999 | 49.659664658911 | 1998 | 49.690256686835 | 1997 | 49.684814716274 | 1996 | 49.664900848099 | 1995 | 49.651573060965 | 1994 | 49.642047086028 | 1993 | 49.626055331287 | 1992 | 49.608258945696 | 1991 | 49.589383141674 | 1990 | 49.567668842656 | 1989 | 49.542876775928 | 1988 | 49.51880016222 | 1987 | 49.495157509185 | 1986 | 49.47244502028 | 1985 | 49.451475015196 | 1984 | 49.430782633647 | 1983 | 49.410852276483 | 1982 | 49.392410856387 | 1981 | 49.374532310303 | 1980 | 49.356654848719 | 1979 | 49.338733685007 | 1978 | 49.32145760501 | 1977 | 49.304156900821 | 1976 | 49.286332228563 | 1975 | 49.26804270798 | 1974 | 49.248927002847 | 1973 | 49.22943800039 | 1972 | 49.210362767534 | 1971 | 49.192096291756 | 1970 | 49.173797766251 | 1969 | 49.15807950454 | 1968 | 49.144018231008 | 1967 | 49.129291908551 | 1966 | 49.116329459524 | 1965 | 49.105283871623 | 1964 | 49.094951805446 | 1963 | 49.084454517359 | 1962 | 49.073697162382 | 1961 | 49.062712910577 | 1960 | 49.050410418414 |
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