Year years 1960 59.195 1961 58.202 1962 58.982 1963 58.037 1964 59.429 1965 59.609 1966 60.024 1967 60.776 1968 60.411 1969 59.891 1970 60.461 1971 60.779 1972 60.162 1973 61.553 1974 60.814 1975 61.92 1976 62.248 1977 62.309 1978 62.643 1979 63.099 1980 63.524 1981 64.374 1982 64.413 1983 65.094 1984 65.268 1985 64.859 1986 65.8 1987 66.253 1988 66.931 1989 66.627 1990 67.563 1991 67.651 1992 68.886 1993 68.91 1994 69.907 1995 70.158 1996 70.564 1997 70.232 1998 72.4 1999 71.042 2000 72.08 2001 73.425 2002 72.921 2003 74.564 2004 74.695 2005 75.403 2006 76.655 2007 77.24 2008 76.057 2009 76.332 2010 76.615 2011 76.886 2012 77.04 2013 77.184 2014 78.11 2015 77.052 2016 78.41 2017 78.56 2018 78.709 2019 78.857 2020 78.672 2021 78.564 2022 78.833