Year years 1960 51.035 1961 52.364 1962 52.79 1963 53.244 1964 53.978 1965 54.712 1966 55.254 1967 55.754 1968 56.207 1969 56.932 1970 57.711 1971 58.524 1972 59.051 1973 59.836 1974 60.552 1975 61.272 1976 61.978 1977 62.354 1978 62.74 1979 63.209 1980 64.012 1981 64.595 1982 65.163 1983 65.789 1984 66.733 1985 67.587 1986 68.419 1987 69.448 1988 69.689 1989 70.122 1990 70.445 1991 70.717 1992 70.885 1993 71.068 1994 71.227 1995 70.948 1996 71.653 1997 72.501 1998 72.862 1999 72.542 2000 72.316 2001 72.613 2002 72.93 2003 73.155 2004 73.08 2005 73.82 2006 74.938 2007 75.187 2008 75.492 2009 75.842 2010 76.131 2011 76.421 2012 76.772 2013 77.083 2014 77.415 2015 77.717 2016 78.049 2017 78.394 2018 78.662 2019 78.975 2020 79.274 2021 78.715 2022 79.68