Year years 1960 65.116 1961 64.681 1962 65.41 1963 66.04 1964 65.922 1965 66.25 1966 66.511 1967 67.113 1968 66.569 1969 66.655 1970 67.092 1971 67.441 1972 66.831 1973 67.815 1974 68.734 1975 69.179 1976 69.143 1977 69.086 1978 69.447 1979 70.409 1980 69.908 1981 69.896 1982 70.574 1983 70.406 1984 70.163 1985 70.156 1986 70.743 1987 71.243 1988 70.756 1989 71.162 1990 70.401 1991 71.399 1992 70.785 1993 71.242 1994 71.322 1995 71.632 1996 71.93 1997 70.872 1998 71.866 1999 70.668 2000 71.761 2001 72.539 2002 73.863 2003 72.824 2004 74.489 2005 74.814 2006 74.204 2007 74.685 2008 74.773 2009 76.757 2010 76.138 2011 76.41 2012 76.704 2013 77.069 2014 77.407 2015 77.93 2016 77.674 2017 77.694 2018 77.353 2019 77.697 2020 77.881 2021 76.403 2022 78.153