Year	% of total population
1960	50.08
1961	49.002
1962	47.347
1963	45.698
1964	44.056
1965	42.432
1966	40.821
1967	39.23
1968	37.66
1969	36.119
1970	34.604
1971	33.769999999999996
1972	33.275000000000006
1973	32.784000000000006
1974	32.297
1975	31.813000000000002
1976	31.333
1977	30.858000000000004
1978	30.385999999999996
1979	29.918999999999997
1980	29.455
1981	29.212999999999994
1982	29.081999999999994
1983	28.950999999999993
1984	28.819999999999993
1985	28.689999999999998
1986	28.560000000000002
1987	28.430000000000007
1988	28.301000000000002
1989	28.171999999999997
1990	28.043999999999997
1991	27.735
1992	27.334999999999994
1993	26.938999999999993
1994	26.546999999999997
1995	26.212999999999994
1996	25.938000000000002
1997	25.524
1998	24.973
1999	24.430999999999997
2000	23.980000000000004
2001	23.622
2002	23.266999999999996
2003	22.915999999999997
2004	22.601
2005	22.325000000000003
2006	22.049999999999997
2007	21.766000000000005
2008	21.474000000000004
2009	21.185000000000002
2010	20.897999999999996
2011	20.545
2012	20.126000000000005
2013	19.714
2014	19.308000000000007
2015	18.909000000000006
2016	18.515
2017	18.129000000000005
2018	17.751999999999995
2019	17.384
2020	17.025999999999996
2021	16.677000000000007
2022	16.336
2023	16.004999999999995