Year % of total population 1960 42.3540895063849 1961 41.6468231108346 1962 40.9180553168154 1963 40.2916928459052 1964 39.7846799889318 1965 39.367227320056 1966 38.9962198172611 1967 38.6278364086575 1968 38.2292736017686 1969 37.768221598893 1970 37.1574782972865 1971 36.4464392394298 1972 35.7785205519543 1973 35.1908675310193 1974 34.6807290148349 1975 34.2239667943638 1976 33.8097790532291 1977 33.3925353631793 1978 32.926227760867 1979 32.4483261996685 1980 31.9469415403472 1981 31.4302741724435 1982 30.9711757184259 1983 30.5603988524219 1984 30.1626059266312 1985 29.7357761944926 1986 29.2497936306207 1987 28.7453468860858 1988 28.2640372858765 1989 27.7949492783392 1990 27.3546250319751 1991 26.9535311312902 1992 26.5535154592403 1993 26.1695350117709 1994 25.7956576735323 1995 25.4349691689205 1996 25.1192030457472 1997 24.831986440815 1998 24.5615302708138 1999 24.298403630652 2000 24.0171398328529 2001 23.7030258099214 2002 23.358011117076 2003 22.9724213942885 2004 22.5333419613171 2005 22.0451844262564 2006 21.5321982329696 2007 21.0178151420762 2008 20.5125612106282 2009 20.0385430146703 2010 19.5544446602161 2011 19.0340322688125 2012 18.501167855116 2013 17.9292329941372 2014 17.3089658022076 2015 16.6542953420247 2016 15.9862943324728 2017 15.3173352724922 2018 14.7241907781503 2019 14.2774128412868 2020 13.9401347581562 2021 13.6501764803891 2022 13.4366639845505 2023 13.3120766895459