Year years 1960 71.31341463414634 1961 71.6448780487805 1962 71.19609756097562 1963 71.18756097560977 1964 72.0778048780488 1965 72.20170731707317 1966 72.33560975609757 1967 72.63658536585366 1968 72.59024390243903 1969 72.61268292682927 1970 73.02024390243903 1971 73.13073170731708 1972 73.64439024390245 1973 73.94097560975611 1974 74.28707317073172 1975 74.66560975609757 1976 74.78536585365855 1977 75.23804878048782 1978 75.18731707317075 1979 75.46609756097561 1980 75.45926829268295 1981 75.69317073170733 1982 76.0339024390244 1983 76.03121951219514 1984 76.60853658536587 1985 76.73365853658538 1986 76.89902439024391 1987 77.19756097560976 1988 77.22658536585367 1989 77.42121951219514 1990 77.24243902439024 1991 77.51463414634145 1992 77.80609756097562 1993 78.08536585365856 1994 78.35000000000001 1995 78.41707317073171 1996 78.89609756097562 1997 79.07951219512196 1998 79.32439024390246 1999 79.58048780487805 2000 79.68048780487806 2001 80.18048780487806 2002 80.38536585365854 2003 80.53658536585368 2004 81.0878048780488 2005 81.23658536585367 2006 81.49024390243903 2007 81.74146341463415 2008 81.99268292682927 2009 82.0439024390244 2010 82.24634146341465 2011 82.69512195121952 2012 82.69756097560976 2013 82.79756097560977 2014 83.19756097560976 2015 82.89756097560976 2016 83.60243902439025 2017 83.55121951219512 2018 83.75365853658538 2019 83.90487804878049 2020 83 2021 83.75121951219514 2022 83.45365853658537