Year % of total population 1960 15.956227220489247 1961 16.36848979724619 1962 16.825095639203045 1963 17.301959880627482 1964 17.772581680741947 1965 18.237431140705606 1966 18.727050365586503 1967 19.19020949977369 1968 19.65077663745147 1969 20.185395472283858 1970 20.709759363511505 1971 20.979357179610272 1972 21.024353819733516 1973 21.068979297948008 1974 21.117163535753697 1975 21.16832084658215 1976 21.22565140357695 1977 21.28873265012104 1978 21.367022363658787 1979 21.463518513589054 1980 21.57828651096865 1981 21.64913235334194 1982 21.616959948309393 1983 21.609361952397762 1984 21.617527555960596 1985 21.636944601740723 1986 21.67036537663293 1987 21.712485894012936 1988 21.765187599670945 1989 21.829889560470185 1990 21.90703542682977 1991 21.990007487481 1992 22.10000157057293 1993 22.203863788716937 1994 22.318293499817997 1995 22.44142276530213 1996 22.571465043289706 1997 22.701364784409687 1998 22.83384574926071 1999 22.96937804670453 2000 23.096695453327293 2001 23.16712742089358 2002 23.133168199950386 2003 23.039022443656194 2004 22.964754934515355 2005 22.898120422223776 2006 22.831898926149123 2007 22.729309431842886 2008 22.68556807524446 2009 22.802274040135416 2010 23.017720566486 2011 23.259635617516892 2012 23.572911797187505 2013 23.983464623425395 2014 24.39416704700225 2015 24.757047242629707 2016 25.084655897756956 2017 25.378469097960917 2018 25.623556634790635 2019 25.671390356139344 2020 25.763539003102565 2021 25.926726018760753 2022 25.89463970493743 2023 25.71402146008702