Year % of total population 1960 23.417904526980436 1961 23.811855220235987 1962 24.204887760480055 1963 24.61209788356428 1964 25.038350654037938 1965 25.45786606166821 1966 25.905530642714965 1967 26.382819453976584 1968 26.89129542510704 1969 27.425762940732273 1970 27.97118389934917 1971 28.396077456533536 1972 28.78835118013504 1973 29.16605232712921 1974 29.522611884242238 1975 29.88379246651239 1976 30.268767881294277 1977 30.663956027687153 1978 31.073065292784435 1979 31.50524410638515 1980 31.967177184783647 1981 32.17801506586074 1982 32.334719262991555 1983 32.474552454533914 1984 32.63029706401366 1985 32.80532938069332 1986 32.99879163740542 1987 33.21052752335172 1988 33.43987713683164 1989 33.684163518037806 1990 33.912664232448996 1991 34.071526350593324 1992 34.191696649273155 1993 34.30875982440467 1994 34.43746258417869 1995 34.587231131268204 1996 34.75469418881693 1997 34.932447586517 1998 35.1302154704147 1999 35.348304469175524 2000 35.57086333384264 2001 35.669739199750474 2002 35.76739374516359 2003 35.86654354624426 2004 35.98024441809437 2005 36.107081755370636 2006 36.24865792398205 2007 36.407280468338456 2008 36.58207594164866 2009 36.75278745400102 2010 36.834326451421376 2011 36.9685328247917 2012 37.10518720552228 2013 37.25548324735614 2014 37.4201646820235 2015 37.5961765249228 2016 37.75601026458188 2017 37.93008806255618 2018 38.13065209839753 2019 38.25143007048052 2020 38.39811521726345 2021 38.59155766137303 2022 38.788220782178676 2023 38.94963891004088