Year years 1960 63.494 1961 63.477 1962 63.504 1963 63.942 1964 64.177 1965 64.494 1966 64.898 1967 65.043 1968 65.128 1969 65.371 1970 65.695 1971 65.916 1972 66.268 1973 66.595 1974 66.965 1975 67.183 1976 66.792 1977 67.103 1978 67.29 1979 67.543 1980 71.9 1981 71.7 1982 71.5 1983 72.4 1984 73.3 1985 73.3 1986 73.6 1987 73.9 1988 73.1 1989 72.9 1990 73.1 1991 72.4 1992 72.3 1993 70.8 1994 70.3 1995 69.4 1996 69.7 1997 69.9 1998 70.4 1999 70.9 2000 71.2 2001 71.3 2002 71.6 2003 71.5 2004 72 2005 71.8 2006 72 2007 72.3 2008 72.4 2009 73.25 2010 73.41 2011 73.57 2012 74.29 2013 75.23 2014 75.82 2015 76.26 2016 76.61 2017 76.92 2018 77.19 2019 77.3 2020 75.53 2021 74.03 2022 78.41