Year % of total population 1960 5.17299909590011 1961 5.4207065079556465 1962 5.673829817619396 1963 5.935349202793824 1964 6.399709536424576 1965 6.8981212538032315 1966 7.436575129795453 1967 8.01686086961714 1968 8.642828487164428 1969 9.307804593171383 1970 10.00981178677859 1971 10.74508289841327 1972 11.519445536978026 1973 12.337158101331022 1974 13.212386219841033 1975 14.09436355309418 1976 14.814250653465292 1977 15.625075850537359 1978 16.479643196253488 1979 16.570235386865637 1980 16.66121936797687 1981 16.753520016711473 1982 16.85388850997623 1983 16.96387112760651 1984 17.088065620353785 1985 17.226837413407665 1986 17.3837861222336 1987 17.54755334506557 1988 17.662536550796496 1989 17.663954186983222 1990 17.648645653345692 1991 17.642400694818747 1992 17.647161457493564 1993 17.661631690372687 1994 17.689962205533362 1995 17.72592581662573 1996 17.767858987535302 1997 17.813846125054148 1998 17.88288535398534 1999 17.901939165884716 2000 17.902125458416744 2001 17.922320229291543 2002 17.962697927951062 2003 18.020080202242703 2004 18.092637098182717 2005 18.176826145618275 2006 18.272664662169447 2007 18.377970198358035 2008 18.49019452196501 2009 18.60406363125758 2010 18.7196123947102 2011 18.843626608166225 2012 18.972930089676336 2013 19.100444215628208 2014 19.18088952408411 2015 19.210597768564735 2016 19.240368087021427 2017 19.26911186792539 2018 19.30171144663597 2019 19.346171272407116 2020 19.4047544009557 2021 19.487508101407773 2022 19.586945450126635 2023 19.694327932423036