Year years 1960 64.845 1961 64.742 1962 65.831 1963 66.671 1964 66.86 1965 65.602 1966 66.569 1967 66.8 1968 66.645 1969 67.418 1970 68.66 1971 68.699 1972 68.628 1973 68.784 1974 68.896 1975 69.047 1976 69.182 1977 69.207 1978 69.279 1979 69.322 1980 69.432 1981 69.652 1982 69.962 1983 69.529 1984 69.678 1985 69.472 1986 70.351 1987 70.49 1988 71.204 1989 71.224 1990 71.463 1991 72.957 1992 72.362 1993 72.533 1994 72.725 1995 72.915 1996 73.093 1997 73.279 1998 73.463 1999 73.635 2000 73.806 2001 73.975 2002 74.142 2003 74.307 2004 74.471 2005 74.634 2006 74.795 2007 74.945 2008 75.115 2009 75.281 2010 75.447 2011 75.14 2012 76.12 2013 76.041 2014 77.11 2015 76.261 2016 76.411 2017 75.826 2018 77.207 2019 76.875 2020 77.021 2021 77.254 2022 77.502