Year	% of total population
1960	26.5
1961	25.617000000000004
1962	24.751999999999995
1963	23.906999999999996
1964	23.081000000000003
1965	22.277
1966	21.492000000000004
1967	20.727999999999994
1968	20.200000000000003
1969	20.200000000000003
1970	20.200000000000003
1971	20.200000000000003
1972	20.200000000000003
1973	20.200000000000003
1974	20.200000000000003
1975	20.200000000000003
1976	20.096999999999994
1977	19.894000000000005
1978	19.691000000000003
1979	19.489999999999995
1980	19.290000000000006
1981	19.316999999999993
1982	19.534000000000006
1983	19.753
1984	19.974000000000004
1985	20.195999999999998
1986	20.376000000000005
1987	20.518
1988	20.661
1989	20.804000000000002
1990	20.948999999999998
1991	21.093999999999994
1992	21.239999999999995
1993	21.385999999999996
1994	21.533
1995	21.680999999999997
1996	21.507000000000005
1997	21.061999999999998
1998	20.622
1999	20.189999999999998
2000	19.763999999999996
2001	19.345
2002	18.933000000000007
2003	18.528000000000006
2004	18.129000000000005
2005	17.738
2006	17.352000000000004
2007	16.977000000000004
2008	16.613
2009	16.257999999999996
2010	15.912999999999997
2011	15.576999999999998
2012	15.251000000000005
2013	14.933999999999997
2014	14.625
2015	14.325999999999993
2016	14.034999999999997
2017	13.751999999999995
2018	13.477999999999994
2019	13.210999999999999
2020	12.951999999999998
2021	12.700999999999993
2022	12.456999999999994
2023	12.221000000000004