Year % of total population 1960 26.178537986543777 1961 26.529338377796705 1962 26.86683640153398 1963 27.217618361894147 1964 27.589237197553402 1965 27.981557843942554 1966 28.32301066298039 1967 28.680150802236348 1968 29.066389788209364 1969 29.468417847893342 1970 29.86181963072149 1971 30.04132137537598 1972 30.18926808072449 1973 30.354830103368503 1974 30.530568850287203 1975 30.721438426871142 1976 30.870309314665814 1977 31.00209275745638 1978 31.140919663095005 1979 31.286116978991274 1980 31.448656862456378 1981 31.58986145469163 1982 31.742936505496775 1983 31.90732778548153 1984 32.092426589023844 1985 32.28770319614823 1986 32.49848010257367 1987 32.74191314913662 1988 32.96390545672743 1989 33.195659513207254 1990 33.41014145667216 1991 33.52423142245471 1992 33.617489774889115 1993 33.7348124609794 1994 33.875028368999864 1995 34.030259521615 1996 34.16845046973506 1997 34.28842199303372 1998 34.42280187569138 1999 34.567446265789506 2000 34.7036804707066 2001 34.78930861847476 2002 34.907489026605944 2003 35.03287564973351 2004 35.16389336567504 2005 35.30632364357515 2006 35.43366388256316 2007 35.57335498028271 2008 35.70740573232893 2009 35.86796606599355 2010 36.04728681897618 2011 36.26829314212253 2012 36.43669720184238 2013 36.589431765492435 2014 36.740703239336945 2015 36.90048175761496 2016 37.044405568760766 2017 37.204605958988246 2018 37.37356880449015 2019 37.46641165780409 2020 37.552277856068706 2021 37.77514871928651 2022 37.91333175942376 2023 37.99200888688161