Year % of total population 1960 7.34287193768231 1961 7.54941923369704 1962 7.7394807364268 1963 7.93556806340482 1964 8.1869513637694 1965 8.45738572430815 1966 8.73002495697535 1967 8.98361634662756 1968 9.22367783607291 1969 9.46255332630323 1970 9.71651937853535 1971 9.97670148576965 1972 10.2202398049781 1973 10.483242738981 1974 10.7618769277042 1975 11.0389087155347 1976 11.3054865422803 1977 11.5251186215807 1978 11.7380899822427 1979 11.9622066121882 1980 12.1117606094733 1981 12.1972411266737 1982 12.2410772661679 1983 12.2615219697395 1984 12.3561187495036 1985 12.5569293927219 1986 12.8394987033152 1987 13.1394336974121 1988 13.4281387738426 1989 13.7481756343114 1990 14.0769653426994 1991 14.3790852670773 1992 14.6783648296965 1993 14.9767018901565 1994 15.2539648634036 1995 15.5129715976123 1996 15.7497236167028 1997 15.9746064579785 1998 16.2219652948958 1999 16.5133765588895 2000 16.7909767864088 2001 17.0280803257256 2002 17.2300155113413 2003 17.382372835075 2004 17.5138597410543 2005 17.6342858612517 2006 17.7526346774596 2007 17.8795913038617 2008 18.0207971087099 2009 18.1969303324261 2010 18.4373980254265 2011 18.788632835441 2012 19.1915929610071 2013 19.6196021688382 2014 20.0796878356174 2015 20.5076482844657 2016 20.8753839804432 2017 21.2074230881658 2018 21.5694413875906 2019 21.9499890252182 2020 22.2651260546645 2021 22.4211110655266 2022 22.3778828900761 2023 22.3041136459572