Year % of total population 1960 15.133040539237829 1961 15.242877848444714 1962 15.336815558537912 1963 15.427453882318222 1964 15.52582576287759 1965 15.633794627406525 1966 15.756387718266843 1967 15.88086563346069 1968 16.0168590911733 1969 16.16120327416055 1970 16.31846397014842 1971 16.42535127092844 1972 16.488368040619427 1973 16.55302659230548 1974 16.628396259995014 1975 16.7101044978998 1976 16.791341631156108 1977 16.874868339226648 1978 16.959382914675068 1979 17.024667230185823 1980 17.063110486406657 1981 17.108375944628747 1982 17.15403962965955 1983 17.20403285632814 1984 17.25244187868409 1985 17.30593731177448 1986 17.361166201301124 1987 17.440067655429335 1988 17.484503669093876 1989 17.539835536002883 1990 17.572356065017644 1991 17.584431419893683 1992 17.597068029910325 1993 17.610380419321118 1994 17.648598609512142 1995 17.709019532468243 1996 17.778806562761293 1997 17.857439622207757 1998 17.933647227547688 1999 18.016072727372702 2000 18.11747591358959 2001 18.230383159620885 2002 18.36401225547789 2003 18.497810867014582 2004 18.62689139100442 2005 18.758045534943538 2006 18.896860419726476 2007 19.04738992562726 2008 19.185124622096172 2009 19.332162867004104 2010 19.48649411501681 2011 19.678048642469673 2012 19.823099671621318 2013 19.932798307614444 2014 20.04195745529075 2015 20.149430436477957 2016 20.25793007701208 2017 20.379814165704268 2018 20.507911222495775 2019 20.60995279987064 2020 20.730557120890275 2021 20.87595515209615 2022 21.11486580409933 2023 21.195274243005198