Year years 1960 73.3 1961 73.6 1962 73.9 1963 74.1 1964 74.3 1965 74.5 1966 74.7 1967 74.9 1968 75.1 1969 75.3 1970 75.5 1971 75.8 1972 76 1973 76.3 1974 76.6 1975 76.9 1976 77.2 1977 77.5 1978 77.7 1979 78 1980 78.2 1981 78.5 1982 78.7 1983 79 1984 79.2 1985 79.5 1986 79.8 1987 80 1988 80.3 1989 80.6 1990 80.8 1991 81.1 1992 81.3 1993 81.5 1994 81.9 1995 81.9 1996 82 1997 82.3 1998 82.6 1999 82.7 2000 83 2001 83 2002 83 2003 82.7 2004 83.8 2005 83.8 2006 84.5 2007 84.8 2008 84.8 2009 85 2010 85.3 2011 85.7 2012 85.4 2013 85.6 2014 86.1 2015 85.6 2016 85.8 2017 85.7 2018 85.8 2019 85.9 2020 85.3 2021 85.5 2022 85.2