Year % of total population 1960 29.2554710438883 1961 29.0864907056833 1962 29.0504328984642 1963 29.0192913952443 1964 29.0231897877707 1965 29.0899582277584 1966 29.1620425346215 1967 29.1936807645246 1968 29.1485969975155 1969 29.0468651828647 1970 28.687502457929 1971 28.3314494417775 1972 28.1330201083042 1973 27.8559459966332 1974 27.5938866713728 1975 27.3688066942466 1976 27.1847159125894 1977 26.9943367145586 1978 26.6927991219278 1979 26.2884686669774 1980 25.826193634369 1981 25.3499631521621 1982 24.9061795469469 1983 24.4919885424325 1984 24.0750584045685 1985 23.6088643719443 1986 23.0695654228169 1987 22.4802270732326 1988 21.8575101438547 1989 21.191166205412 1990 20.4554784055633 1991 19.6920005982126 1992 19.0397117633097 1993 18.5605722839326 1994 18.141480756165 1995 17.725554193591 1996 17.3554283482418 1997 17.039816894425 1998 16.7723480783351 1999 16.568199583148 2000 16.3590793588215 2001 16.1899855753364 2002 16.1167571756779 2003 16.057852012588 2004 15.9813691767727 2005 15.8918893852312 2006 15.7717700862765 2007 15.6204726095213 2008 15.4748049574516 2009 15.337634707893 2010 15.1728008789996 2011 14.9932616022261 2012 14.8404888536361 2013 14.6782202935916 2014 14.4694002097542 2015 14.235026593914 2016 14.0486712495692 2017 13.9039129645997 2018 13.7585053599013 2019 13.6276627142885 2020 13.4956608643372 2021 13.3432969524212 2022 13.1825264960644 2023 13.015489960825