Year years 1960 60.423 1961 60.755 1962 61.058 1963 61.334 1964 61.583 1965 61.819 1966 61.988 1967 62.153 1968 62.319 1969 62.499 1970 62.684 1971 62.803 1972 62.935 1973 63.066 1974 63.233 1975 63.445 1976 63.705 1977 63.941 1978 64.132 1979 64.448 1980 64.749 1981 65.023 1982 65.385 1983 65.614 1984 65.966 1985 66.315 1986 66.656 1987 67.012 1988 67.319 1989 67.469 1990 67.944 1991 68.173 1992 68.395 1993 68.633 1994 68.824 1995 69.009 1996 69.202 1997 69.325 1998 69.478 1999 69.634 2000 69.75 2001 69.9 2002 70.025 2003 70.297 2004 70.481 2005 70.527 2006 70.781 2007 71.106 2008 71.384 2009 71.635 2010 71.887 2011 72.131 2012 72.454 2013 72.757 2014 72.878 2015 73.191 2016 73.534 2017 73.644 2018 73.568 2019 73.621 2020 73.182 2021 70.262 2022 70.475