Year | Value | 2021 | 48.687493411111 | 2020 | 48.687493411111 | 2019 | 48.687493411111 | 2018 | 48.668166004849 | 2017 | 48.648838598587 | 2016 | 48.629511192325 | 2015 | 48.610183786063 | 2014 | 48.589099342868 | 2013 | 48.569771936606 | 2012 | 48.550444530344 | 2011 | 48.531117124082 | 2010 | 47.984678637945 | 2009 | 47.940752714622 | 2008 | 47.589345328039 | 2007 | 47.562989774045 | 2006 | 47.534877183118 | 2005 | 47.443511262607 | 2004 | 47.425940893278 | 2003 | 47.218610535193 | 2002 | 47.12021646695 | 2001 | 47.157114242541 | 2000 | 46.861932037811 | 1999 | 47.222124609059 | 1998 | 46.4876831711 | 1997 | 46.726640193977 | 1996 | 46.47538391257 | 1995 | 47.823031240117 | 1994 | 47.847629757178 | 1993 | 47.158871279474 | 1992 | 47.566503847911 | 1991 | 47.223881645992 | 1990 | 47.03587869417 | 1989 | 47.533120146186 | 1988 | 46.846118705415 | 1987 | 46.447271321643 | 1986 | 46.338335031802 | 1985 | 46.304951330077 | 1984 | 44.813226974031 | 1983 | 44.945004744 | 1982 | 44.945004744 | 1981 | 44.945004744 | 1980 | 44.945004744 | 1979 | 44.945004744 | 1978 | 44.945004744 | 1977 | 44.945004744 | 1976 | 44.941490670134 | 1975 | 44.930948448536 | 1974 | 44.391538110131 | 1973 | 44.382752925466 | 1972 | 44.373967740802 | 1971 | 44.365182556137 | 1970 | 44.356397371473 | 1969 | 44.347612186808 | 1968 | 44.338827002144 | 1967 | 44.330041817479 | 1966 | 44.321256632814 | 1965 | 44.31247144815 | 1964 | 44.303686263485 | 1963 | 44.294901078821 | 1962 | 44.286115894156 | 1961 | 44.277330709492 |
|