Year	% of total population
1960	72.67699999999999
1961	71.803
1962	70.911
1963	70.002
1964	69.076
1965	66.334
1966	63.302
1967	60.161
1968	56.93
1969	53.648
1970	50.329
1971	47.008
1972	43.708
1973	40.472
1974	38.763
1975	37.215
1976	35.69
1977	34.19799999999999
1978	32.735
1979	31.304000000000002
1980	29.906000000000006
1981	28.549000000000007
1982	27.227000000000004
1983	25.944999999999993
1984	24.700000000000003
1985	24.549999999999997
1986	24.495000000000005
1987	24.439999999999998
1988	24.385999999999996
1989	24.331000000000003
1990	24.277
1991	24.223
1992	24.168000000000006
1993	24.114000000000004
1994	24.060000000000002
1995	24.006
1996	23.951999999999998
1997	23.885999999999996
1998	23.807000000000002
1999	23.715999999999994
2000	23.613
2001	23.498000000000005
2002	23.370999999999995
2003	23.232
2004	23.081000000000003
2005	22.92
2006	22.747
2007	22.563000000000002
2008	22.367999999999995
2009	22.162999999999997
2010	21.947999999999993
2011	21.723
2012	21.488
2013	21.244
2014	20.991
2015	20.730000000000004
2016	20.459999999999994
2017	20.183000000000007
2018	19.897999999999996
2019	19.607
2020	19.308999999999997
2021	19.006
2022	18.697999999999993
2023	18.394000000000005