Year years 1960 48.525 1961 49.703 1962 50.213 1963 50.723 1964 51.478 1965 52.175 1966 52.706 1967 53.234 1968 53.735 1969 54.345 1970 55.031 1971 55.729 1972 56.234 1973 56.892 1974 57.52 1975 58.131 1976 58.772 1977 59.089 1978 59.344 1979 59.633 1980 60.242 1981 60.796 1982 61.534 1983 62.272 1984 63.193 1985 64.07 1986 64.941 1987 66.047 1988 66.226 1989 66.563 1990 66.759 1991 66.94 1992 67.03 1993 67.065 1994 67.121 1995 66.544 1996 67.205 1997 68.228 1998 68.746 1999 68.575 2000 68.434 2001 68.798 2002 69.13 2003 69.371 2004 69.33 2005 70.039 2006 70.952 2007 71.162 2008 71.45 2009 71.817 2010 72.092 2011 72.352 2012 72.68 2013 72.958 2014 73.27 2015 73.544 2016 73.688 2017 74.071 2018 74.315 2019 74.638 2020 74.954 2021 74.518 2022 75.473