Year years 1960 57.015 1961 57.537 1962 57.771 1963 57.15 1964 58.738 1965 59.455 1966 59.689 1967 60.72 1968 61.63 1969 61.905 1970 62.491 1971 62.732 1972 62.281 1973 63.905 1974 64.901 1975 66.279 1976 65.855 1977 67.402 1978 68.074 1979 68.186 1980 68.84 1981 69.909 1982 70.299 1983 70.011 1984 70.46 1985 71.176 1986 71.81 1987 72.54 1988 72.456 1989 72.467 1990 72.574 1991 73.574 1992 74.135 1993 74.195 1994 74.614 1995 74.609 1996 74.899 1997 75.596 1998 75.669 1999 76.018 2000 76.87 2001 76.773 2002 77.445 2003 77.387 2004 77.616 2005 78.016 2006 78.261 2007 77.826 2008 78.484 2009 78.741 2010 78.501 2011 79.11 2012 79.023 2013 79.339 2014 79.473 2015 79.746 2016 80.079 2017 80.35 2018 80.133 2019 80.326 2020 79.377 2021 78.944 2022 79.519