Year years 1960 60.809 1961 61.464 1962 62.121 1963 58.151 1964 58.669 1965 63.95 1966 64.47 1967 64.822 1968 65.344 1969 65.551 1970 66.003 1971 66.473 1972 66.861 1973 67.368 1974 44.709 1975 67.781 1976 68.401 1977 68.638 1978 69.209 1979 69.439 1980 69.498 1981 69.573 1982 69.59 1983 70.196 1984 70.151 1985 70.505 1986 70.768 1987 71.037 1988 71.048 1989 71.445 1990 71.722 1991 71.975 1992 72.255 1993 72.627 1994 72.932 1995 73.142 1996 73.509 1997 73.763 1998 74 1999 74.255 2000 74.601 2001 74.977 2002 75.37 2003 75.621 2004 75.815 2005 75.953 2006 76.255 2007 76.656 2008 76.813 2009 77.109 2010 77.362 2011 77.736 2012 78.091 2013 78.409 2014 78.817 2015 79.051 2016 78.945 2017 79.246 2018 79.67 2019 79.508 2020 79.345 2021 79.209 2022 80.068