Year | Value | 2022 | 50.741754219565 | 2021 | 50.761167236992 | 2020 | 50.782823750394 | 2019 | 50.80098820075 | 2018 | 50.814683935513 | 2017 | 50.827760220686 | 2016 | 50.841924376183 | 2015 | 50.855332815062 | 2014 | 50.864440978093 | 2013 | 50.872663992121 | 2012 | 50.882415008521 | 2011 | 50.891957351735 | 2010 | 50.901391311907 | 2009 | 50.911635091607 | 2008 | 50.92344274422 | 2007 | 50.933730081664 | 2006 | 50.941003647746 | 2005 | 50.945668157139 | 2004 | 50.948147845571 | 2003 | 50.949807229724 | 2002 | 50.950613563073 | 2001 | 50.950715802138 | 2000 | 50.949687907288 | 1999 | 50.94812185969 | 1998 | 50.945892159679 | 1997 | 50.941832893142 | 1996 | 50.93967087493 | 1995 | 50.942085653232 | 1994 | 50.945424203677 | 1993 | 50.949220945896 | 1992 | 50.954263731056 | 1991 | 50.956905778714 | 1990 | 50.957837789053 | 1989 | 50.960899624909 | 1988 | 50.965504546001 | 1987 | 50.971864922081 | 1986 | 50.978192951622 | 1985 | 50.994941199736 | 1984 | 51.019012604743 | 1983 | 51.040166087881 | 1982 | 51.059667572935 | 1981 | 51.070777258078 | 1980 | 51.070519838822 | 1979 | 51.072271490129 | 1978 | 51.081791663836 | 1977 | 51.089104351051 | 1976 | 51.097189898219 | 1975 | 51.103962780482 | 1974 | 51.100016941161 | 1973 | 51.090537885589 | 1972 | 51.080941496545 | 1971 | 51.083549439452 | 1970 | 51.090212253808 | 1969 | 51.090283841245 | 1968 | 51.094490131224 | 1967 | 51.099249322522 | 1966 | 51.103802235714 | 1965 | 51.110745747731 | 1964 | 51.115597553475 | 1963 | 51.116260900116 | 1962 | 51.117144520048 | 1961 | 51.118668605383 | 1960 | 51.121060099807 |
|