Year years 1960 55.017 1961 55.831 1962 56.599 1963 57.31 1964 57.947 1965 58.499 1966 58.981 1967 59.42 1968 59.835 1969 60.25 1970 60.69 1971 61.155 1972 61.614 1973 62.055 1974 62.459 1975 62.81 1976 63.123 1977 63.434 1978 63.778 1979 64.189 1980 64.703 1981 65.313 1982 65.975 1983 66.644 1984 67.29 1985 67.874 1986 68.388 1987 68.844 1988 69.253 1989 69.623 1990 69.971 1991 70.298 1992 70.616 1993 70.942 1994 71.279 1995 71.646 1996 72.037 1997 72.445 1998 72.845 1999 73.225 2000 73.569 2001 73.867 2002 74.106 2003 74.274 2004 74.372 2005 74.376 2006 74.331 2007 74.238 2008 74.152 2009 74.119 2010 74.19 2011 74.365 2012 74.574 2013 74.739 2014 74.797 2015 74.682 2016 74.412 2017 74.138 2018 74.015 2019 74.202 2020 70.133 2021 70.213 2022 74.832