Year years 1960 54.172 1961 55.228 1962 56.307 1963 57.233 1964 58.309 1965 59.275 1966 60.217 1967 61.123 1968 61.879 1969 62.167 1970 62.321 1971 62.517 1972 62.461 1973 62.63 1974 63.253 1975 63.451 1976 63.555 1977 63.903 1978 64.85 1979 64.937 1980 65.823 1981 66.385 1982 67.05 1983 67.884 1984 67.923 1985 67.403 1986 67.586 1987 67.523 1988 67.731 1989 67.912 1990 68.095 1991 68.265 1992 68.127 1993 68.588 1994 68.58 1995 68.582 1996 68.752 1997 69.057 1998 69.018 1999 68.748 2000 68.446 2001 68.451 2002 68.541 2003 68.704 2004 68.972 2005 69.204 2006 69.442 2007 69.652 2008 69.849 2009 69.844 2010 69.929 2011 70.261 2012 70.208 2013 69.894 2014 69.862 2015 70.107 2016 69.911 2017 69.793 2018 70.023 2019 70.1 2020 70.042 2021 67.838 2022 68.005