Year | Value | 2022 | 49.875527216358 | 2021 | 49.87101187604 | 2020 | 49.868191516641 | 2019 | 49.861604886849 | 2018 | 49.851896659483 | 2017 | 49.841133880817 | 2016 | 49.827544542488 | 2015 | 49.815444951441 | 2014 | 49.804572596306 | 2013 | 49.792195665388 | 2012 | 49.779091436927 | 2011 | 49.766302524349 | 2010 | 49.75401493387 | 2009 | 49.741475792517 | 2008 | 49.72854406923 | 2007 | 49.715398962495 | 2006 | 49.70178295906 | 2005 | 49.687502369731 | 2004 | 49.673620253231 | 2003 | 49.659973758625 | 2002 | 49.64579374694 | 2001 | 49.63338557758 | 2000 | 49.622909283141 | 1999 | 49.613704304376 | 1998 | 49.604526120501 | 1997 | 49.594413844853 | 1996 | 49.583715276335 | 1995 | 49.571911813872 | 1994 | 49.558381123558 | 1993 | 49.541959319674 | 1992 | 49.524372302039 | 1991 | 49.50613102588 | 1990 | 49.48513278486 | 1989 | 49.461296743811 | 1988 | 49.435279634238 | 1987 | 49.406890325338 | 1986 | 49.374767124783 | 1985 | 49.33986818375 | 1984 | 49.305510712967 | 1983 | 49.273158921775 | 1982 | 49.245770911992 | 1981 | 49.216778524706 | 1980 | 49.180324020577 | 1979 | 49.146435981273 | 1978 | 49.115773954707 | 1977 | 49.084518377673 | 1976 | 49.053267505727 | 1975 | 49.019313092665 | 1974 | 48.981715282798 | 1973 | 48.943016176746 | 1972 | 48.903438565245 | 1971 | 48.861988577637 | 1970 | 48.818177324 | 1969 | 48.773494201296 | 1968 | 48.729116252744 | 1967 | 48.684245099695 | 1966 | 48.638855629393 | 1965 | 48.593202282004 | 1964 | 48.5471118887 | 1963 | 48.501219067083 | 1962 | 48.456392263644 | 1961 | 48.544320531964 | 1960 | 48.776479167611 |
|