Year years 1960 57.588 1961 58.199 1962 58.934 1963 59.552 1964 60.219 1965 60.805 1966 61.154 1967 61.576 1968 61.772 1969 61.538 1970 61.713 1971 61.796 1972 61.784 1973 61.022 1974 61.686 1975 61.852 1976 61.975 1977 62.273 1978 62.527 1979 62.941 1980 62.734 1981 62.729 1982 62.793 1983 63.29 1984 63.892 1985 64.526 1986 64.715 1987 64.936 1988 65.149 1989 65.277 1990 65.508 1991 65.643 1992 65.827 1993 65.928 1994 66.125 1995 66.286 1996 66.408 1997 66.448 1998 66.68 1999 66.763 2000 66.31 2001 66.34 2002 65.748 2003 66.177 2004 66.424 2005 66.632 2006 66.855 2007 66.826 2008 66.935 2009 67.089 2010 67.328 2011 67.523 2012 67.552 2013 67.428 2014 67.376 2015 66.844 2016 67.24 2017 67.79 2018 67.81 2019 67.893 2020 67.924 2021 67.114 2022 68.312