Year | Value | 2021 | 66.377295844415 | 2020 | 67.941652879153 | 2019 | 69.018929648766 | 2018 | 68.822726522728 | 2017 | 68.586752006265 | 2016 | 68.269895278929 | 2015 | 67.930247291561 | 2014 | 67.516725439774 | 2013 | 67.03811040059 | 2012 | 66.676167651456 | 2011 | 66.334674448803 | 2010 | 65.939568118125 | 2009 | 65.616705345297 | 2008 | 65.246171438165 | 2007 | 65.078989365057 | 2006 | 64.837840290455 | 2005 | 64.523050321689 | 2004 | 64.147327284791 | 2003 | 63.940311299891 | 2002 | 63.70076369861 | 2001 | 63.32181162911 | 2000 | 63.044477531932 | 1999 | 62.702975041928 | 1998 | 62.314237557259 | 1997 | 61.895343338711 | 1996 | 61.551840041553 | 1995 | 61.220525038599 | 1994 | 60.803881177909 | 1993 | 60.522786039597 | 1992 | 60.230799512779 | 1991 | 59.753575327216 | 1990 | 59.452807242828 | 1989 | 59.119719810357 | 1988 | 58.663281417945 | 1987 | 58.316468744817 | 1986 | 57.729353221908 | 1985 | 57.290641871671 | 1984 | 56.77947030845 | 1983 | 56.201120126133 | 1982 | 55.792168139782 | 1981 | 55.367722227182 | 1980 | 55.040144024607 | 1979 | 54.561622901738 | 1978 | 54.06350476505 | 1977 | 53.673168521039 | 1976 | 53.195817893393 | 1975 | 52.72962881293 | 1974 | 52.329205817379 | 1973 | 51.870674644649 | 1972 | 51.450500043274 | 1971 | 49.265249375953 | 1970 | 50.26447438712 | 1969 | 50.293712357493 | 1968 | 49.888177044374 | 1967 | 48.830758815227 | 1966 | 48.176519770381 | 1965 | 47.07495949373 | 1964 | 48.266580738264 | 1963 | 47.823961995436 | 1962 | 47.414322782446 | 1961 | 46.990265941935 | 1960 | 46.507799182263 |
|