Year years 1960 47.741 1961 48.434 1962 49.254 1963 50.049 1964 50.859 1965 51.659 1966 52.461 1967 53.208 1968 54.239 1969 55.163 1970 56.072 1971 56.978 1972 57.797 1973 58.594 1974 59.356 1975 58.078 1976 60.749 1977 60.864 1978 61.911 1979 62.388 1980 62.8 1981 63.161 1982 63.509 1983 63.762 1984 63.998 1985 64.29 1986 63.76 1987 64.764 1988 64.973 1989 65.186 1990 65.392 1991 65.579 1992 65.767 1993 65.958 1994 66.188 1995 66.381 1996 66.59 1997 66.742 1998 66.92 1999 67.069 2000 67.225 2001 67.364 2002 67.515 2003 67.644 2004 67.801 2005 67.936 2006 68.09 2007 67.986 2008 68.404 2009 68.466 2010 68.732 2011 68.908 2012 69.084 2013 69.188 2014 69.234 2015 69.583 2016 69.801 2017 69.988 2018 70.173 2019 70.382 2020 70.199 2021 70.348 2022 70.742