Year years 1960 62.302 1961 62.971 1962 63.543 1963 64.019 1964 64.548 1965 64.919 1966 65.298 1967 65.435 1968 65.735 1969 65.931 1970 65.891 1971 66.153 1972 66.518 1973 66.745 1974 67.183 1975 67.605 1976 67.94 1977 68.366 1978 68.813 1979 69.173 1980 69.404 1981 69.736 1982 69.98 1983 70.115 1984 70.122 1985 70.143 1986 70.093 1987 70.184 1988 70.076 1989 70.12 1990 70.165 1991 70.219 1992 70.278 1993 70.387 1994 70.364 1995 70.526 1996 70.772 1997 70.787 1998 71.006 1999 71.418 2000 71.63 2001 71.881 2002 72.065 2003 72.091 2004 72.433 2005 72.652 2006 72.751 2007 73.002 2008 73.137 2009 73.357 2010 73.567 2011 73.785 2012 73.989 2013 74.163 2014 74.342 2015 74.54 2016 74.737 2017 74.863 2018 75.013 2019 75.23 2020 75.418 2021 75.629 2022 75.677