Year years 1960 53.364 1961 53.895 1962 54.401 1963 54.88 1964 55.305 1965 55.664 1966 55.942 1967 56.213 1968 56.487 1969 56.654 1970 57.152 1971 57.633 1972 58.205 1973 58.837 1974 59.526 1975 60.232 1976 60.89 1977 61.559 1978 62.153 1979 62.696 1980 63.191 1981 63.662 1982 64.11 1983 64.528 1984 65.171 1985 65.811 1986 66.535 1987 67.3 1988 68.056 1989 68.749 1990 69.348 1991 69.625 1992 70.117 1993 70.345 1994 70.757 1995 71.041 1996 71.362 1997 71.681 1998 72.045 1999 72.463 2000 72.839 2001 73.24 2002 73.613 2003 73.975 2004 74.279 2005 74.514 2006 74.689 2007 74.844 2008 74.983 2009 75.184 2010 75.43 2011 75.743 2012 76.062 2013 76.369 2014 76.622 2015 76.789 2016 76.763 2017 76.972 2018 77.094 2019 77.297 2020 72.153 2021 73.67 2022 77.894