Year % of total population 1960 3.51727588817182 1961 3.52512624800495 1962 3.53236852370301 1963 3.5418346078709 1964 3.55374646951321 1965 3.56683423397856 1966 3.58072471497796 1967 3.58324993368892 1968 3.59109715769128 1969 3.62179134075135 1970 3.66473351612644 1971 3.71989753719898 1972 3.78669445891958 1973 3.8613647394285 1974 3.94378741234034 1975 4.03001756916968 1976 4.11776620921403 1977 4.20473449784003 1978 4.28689494817959 1979 4.35429063601186 1980 4.37458882580834 1981 4.35861893483596 1982 4.36272793675903 1983 4.37892667860026 1984 4.37491197532164 1985 4.34966058831359 1986 4.30675425054654 1987 4.25246448930742 1988 4.18886978811207 1989 4.11955651311775 1990 4.06453902518794 1991 4.0458807489424 1992 4.02249941775692 1993 3.98300950966723 1994 3.9541394171013 1995 3.92756332937476 1996 3.90248590142377 1997 3.87984547544418 1998 3.85912446531604 1999 3.86746156045236 2000 3.88816178628151 2001 3.87966210307426 2002 3.85763629891583 2003 3.8428077806816 2004 3.90017439454464 2005 4.0188431252457 2006 4.12903172457135 2007 4.21827218209773 2008 4.27058022668295 2009 4.27872365924609 2010 4.25091155201639 2011 4.2058261033727 2012 4.1608934303797 2013 4.13058475748596 2014 4.12174718588549 2015 4.13152007866171 2016 4.1477717385478 2017 4.1946973993782 2018 4.26541596919286 2019 4.32055687458438 2020 4.33403294110642 2021 4.30378560548571 2022 4.27833816438977 2023 4.29516181087346