Year years 1960 65.673 1961 65.954 1962 65.989 1963 66.809 1964 66.981 1965 67.409 1966 67.909 1967 68.092 1968 68.063 1969 68.213 1970 68.635 1971 68.73 1972 69.011 1973 69.445 1974 69.667 1975 69.837 1976 70.007 1977 69.917 1978 70.081 1979 70.215 1980 70.686 1981 71.04 1982 71.369 1983 71.207 1984 71.45 1985 71.609 1986 71.799 1987 72.141 1988 72.427 1989 73.184 1990 73.359 1991 73.364 1992 73.287 1993 73.041 1994 72.963 1995 72.837 1996 73.025 1997 72.764 1998 72.716 1999 72.807 2000 72.816 2001 72.758 2002 73.168 2003 73.261 2004 73.581 2005 73.735 2006 73.797 2007 73.684 2008 73.604 2009 74.139 2010 74.667 2011 74.997 2012 74.819 2013 74.555 2014 74.21 2015 73.971 2016 73.917 2017 73.912 2018 73.903 2019 73.874 2020 73.918 2021 72.543 2022 72.737