Year % of total population 1960 43.6858814192069 1961 43.9720544356306 1962 44.5986766398159 1963 45.1815801457195 1964 45.713601532567 1965 46.203819880106 1966 46.6672178814062 1967 47.1032026534718 1968 47.50933247702 1969 47.8930830013542 1970 48.1729244808786 1971 48.349026834625 1972 48.5124018061483 1973 48.6807643806383 1974 48.8353585385264 1975 48.9591687297325 1976 49.0599241581326 1977 49.146723662499 1978 49.2213384560593 1979 49.3090710083459 1980 49.4321571854747 1981 49.6027024301704 1982 49.7597368499272 1983 49.8762786166585 1984 49.9880379341034 1985 50.0745729642519 1986 50.1266450085348 1987 50.1630678254637 1988 50.1951743470174 1989 50.2328749627485 1990 50.2829412595664 1991 50.3071073413279 1992 50.2992486947663 1993 50.2863116506218 1994 50.2701544395635 1995 50.2543640148185 1996 50.2355773491271 1997 50.2150287673621 1998 50.1974390156664 1999 50.1798206025048 2000 50.1649108646339 2001 50.1552051853574 2002 50.1431517408453 2003 50.1300711489185 2004 50.1214354109463 2005 50.1181345868382 2006 50.1179665107859 2007 50.1186375813241 2008 50.1160892853038 2009 50.1145243869577 2010 50.1163952607364 2011 50.1042764077315 2012 50.0889829616057 2013 50.0823196065174 2014 50.0782290363904 2015 50.0750780612955 2016 50.0728136361859 2017 50.0740256494068 2018 50.0780717692482 2019 50.0822464223971 2020 50.09490443238 2021 50.1113815344207 2022 50.12402146187 2023 50.1406045131461