Year % of total population 1960 9.79331315487632 1961 10.031232191275452 1962 10.194197465135856 1963 10.309382054733566 1964 10.43735956198526 1965 10.57596685819405 1966 10.694814867716122 1967 10.807532354347675 1968 10.923709947013515 1969 11.040516545801914 1970 11.159905070518738 1971 11.283086121855764 1972 11.427365583381548 1973 11.575407632454835 1974 11.73073844785279 1975 11.834699966872673 1976 11.996246791169765 1977 12.168674854897244 1978 12.34847902409361 1979 12.528243978976473 1980 12.709573532627596 1981 12.852468084048457 1982 12.968093483816862 1983 13.105054919177006 1984 13.251302347231046 1985 13.40258969689446 1986 13.557777185490414 1987 13.711800719518191 1988 13.875523775329365 1989 14.045455502497408 1990 14.226352055452452 1991 14.439026964238659 1992 14.639840900181706 1993 14.850625464002942 1994 15.081131750787895 1995 15.331898054851553 1996 15.6082134129776 1997 15.892793357630932 1998 16.19771817519807 1999 16.52607720535571 2000 16.886422590903727 2001 17.141141624785348 2002 17.343977617543295 2003 17.55417500169512 2004 17.768921912740876 2005 17.988054391699812 2006 18.219403776216808 2007 18.454295657893475 2008 18.715669947415886 2009 18.983260223142324 2010 19.24509049628163 2011 19.45815350810403 2012 19.65860809977155 2013 19.86659170375477 2014 20.08565733312334 2015 20.32515544783982 2016 20.573058019636612 2017 20.816382704045107 2018 21.07531133500162 2019 21.318404104974675 2020 21.576415543158674 2021 21.855039901431084 2022 22.165299071199264 2023 22.44354345923591