Year years 1960 73.00560975609757 1961 73.47439024390245 1962 73.35048780487806 1963 73.55536585365854 1964 73.73317073170732 1965 73.86170731707317 1966 74.07853658536585 1967 74.12243902439026 1968 73.97292682926829 1969 74.08487804878051 1970 74.64926829268293 1971 74.6239024390244 1972 74.71804878048782 1973 74.86731707317074 1974 74.98048780487805 1975 74.98463414634148 1976 74.96926829268294 1977 75.37975609756099 1978 75.46902439024392 1979 75.52414634146342 1980 75.7409756097561 1981 76.02609756097561 1982 76.32731707317075 1983 76.55170731707317 1984 76.81585365853661 1985 76.6678048780488 1986 76.93121951219513 1987 77.09219512195124 1988 76.97926829268293 1989 77.72682926829269 1990 77.53682926829269 1991 77.66682926829269 1992 77.99878048780488 1993 78.06048780487805 1994 78.65024390243903 1995 78.74048780487806 1996 78.9590243902439 1997 79.19756097560978 1998 79.33902439024392 1999 79.44146341463416 2000 79.6439024390244 2001 79.79512195121951 2002 79.84634146341465 2003 80.09512195121953 2004 80.49756097560977 2005 80.54634146341465 2006 80.7487804878049 2007 80.90000000000002 2008 81.10000000000001 2009 81.35121951219513 2010 81.45121951219514 2011 81.80243902439025 2012 81.7048780487805 2013 81.9560975609756 2014 82.25365853658538 2015 82.2048780487805 2016 82.30731707317074 2017 82.40975609756099 2018 82.55853658536586 2019 83.10975609756099 2020 82.35609756097561 2021 83.05609756097562 2022 83.10975609756099