Year % of total population 1960 68.0880929948308 1961 67.6662339262193 1962 67.3155084226455 1963 67.0057212559519 1964 66.6378133584178 1965 66.2539342741226 1966 65.9087054472647 1967 65.6092287656883 1968 65.4194599261526 1969 65.3370442741051 1970 65.2916526689888 1971 65.4054955032671 1972 65.7021002399738 1973 65.9233188043049 1974 66.0918019164056 1975 66.3123309671682 1976 66.6005411799747 1977 66.8795435799886 1978 67.0923009175532 1979 67.3374075584407 1980 67.6583063223557 1981 68.0459183533485 1982 68.467481233905 1983 68.9529485648142 1984 69.3738987559445 1985 69.597043109047 1986 69.7270282749817 1987 69.8045888755595 1988 69.7334454465605 1989 69.554502067919 1990 69.334048493639 1991 69.0506044925123 1992 68.742145914854 1993 68.4111949281253 1994 68.0653959086517 1995 67.7530538925094 1996 67.4915265312444 1997 67.291529989018 1998 67.1472601567378 1999 67.0253884664789 2000 67.104502006299 2001 67.2211526585299 2002 67.191545426513 2003 67.2664209601608 2004 67.3571966093513 2005 67.4533918312952 2006 67.6087285551441 2007 67.7775265515449 2008 67.9863620224073 2009 68.1934769858677 2010 68.403936738455 2011 68.7372396305716 2012 69.0202031910092 2013 69.1019775699248 2014 69.1581717752907 2015 69.2609422952806 2016 69.424754564576 2017 69.5349100468318 2018 69.5485209232242 2019 69.5306085910193 2020 69.4608736206168 2021 69.3411447457537 2022 69.1715861204233 2023 68.9566907337337