Year % of total population 1960 20.316397944088884 1961 20.627671017222266 1962 20.937972509972976 1963 21.183736313309375 1964 21.405798626389394 1965 21.632473276522955 1966 21.87075782518312 1967 22.123259468482562 1968 22.391368472909402 1969 22.67033300185723 1970 22.961556999435814 1971 23.255554378500975 1972 23.540555889570843 1973 23.75323247495316 1974 23.951864028379784 1975 24.151865571577183 1976 24.357297284864934 1977 24.560953292455906 1978 24.764205623775375 1979 24.9584002213765 1980 25.13462547809096 1981 25.28749258290158 1982 25.429362932000032 1983 25.63563403081289 1984 25.843743782527202 1985 26.048635864028206 1986 26.255388092552668 1987 26.466348404006368 1988 26.68419329020088 1989 26.911427362419545 1990 27.15471910070839 1991 27.413701932535446 1992 27.69375441162614 1993 28.213748477612295 1994 28.805501567080828 1995 29.430091810951414 1996 30.092440978806813 1997 30.789020749896906 1998 31.52854838142936 1999 32.31715045132034 2000 33.17236615891389 2001 34.124129504114045 2002 35.20005251099402 2003 36.38605603246175 2004 37.648449391136865 2005 38.9728966027726 2006 40.37151232908888 2007 41.84229568284901 2008 43.37725069387021 2009 44.133982303429995 2010 44.843119134530255 2011 45.49720659301885 2012 46.13861951114594 2013 46.7709917257943 2014 47.40139960441465 2015 48.03287498280174 2016 48.67131617308547 2017 49.32715528391272 2018 50.00830316258927 2019 50.21664538548545 2020 50.411176221294376 2021 50.63261890757763 2022 50.9135133253814 2023 51.162263660376325