Year years 1960 62.896 1961 63.185 1962 63.433 1963 63.732 1964 64.05 1965 64.362 1966 64.659 1967 64.948 1968 65.328 1969 65.646 1970 65.926 1971 66.151 1972 66.413 1973 66.488 1974 67.001 1975 67.221 1976 67.84 1977 67.88 1978 67.562 1979 67.366 1980 67.521 1981 67.746 1982 68.436 1983 69.161 1984 69.351 1985 69.257 1986 69.285 1987 68.924 1988 69.215 1989 69.598 1990 70.133 1991 69.616 1992 70.668 1993 70.656 1994 70.851 1995 70.763 1996 70.71 1997 71.054 1998 71.456 1999 71.771 2000 72.041 2001 72.11 2002 72.232 2003 72.402 2004 72.478 2005 72.765 2006 72.855 2007 72.678 2008 72.667 2009 72.579 2010 72.731 2011 72.564 2012 72.753 2013 73.024 2014 73.366 2015 73.104 2016 73.537 2017 73.632 2018 73.806 2019 71.205 2020 72.677 2021 71.598 2022 74.358