Year	% of total population
1960	42.467
1961	41.696
1962	40.928
1963	40.164
1964	39.404
1965	38.652
1966	37.903
1967	37.161
1968	36.423
1969	35.693
1970	35.053
1971	34.516999999999996
1972	33.983000000000004
1973	33.455
1974	32.931
1975	32.411
1976	31.894000000000005
1977	31.382999999999996
1978	30.876000000000005
1979	30.503
1980	30.289
1981	30.075999999999993
1982	29.864000000000004
1983	29.653000000000006
1984	29.441999999999993
1985	29.233000000000004
1986	29.025000000000006
1987	28.816999999999993
1988	28.61
1989	28.584999999999994
1990	28.769000000000005
1991	28.953999999999994
1992	29.14
1993	29.325999999999993
1994	29.513000000000005
1995	29.700000000000003
1996	29.888999999999996
1997	30.076999999999998
1998	30.266999999999996
1999	30.456999999999994
2000	30.632000000000005
2001	30.757999999999996
2002	30.884
2003	31.010999999999996
2004	31.138000000000005
2005	31.265
2006	31.393
2007	31.521
2008	31.649
2009	31.777
2010	31.906000000000006
2011	32.035
2012	32.025999999999996
2013	31.878
2014	31.730999999999995
2015	31.584000000000003
2016	31.436999999999998
2017	31.283
2018	31.120000000000005
2019	30.948999999999998
2020	30.771
2021	30.584999999999994
2022	30.391000000000005
2023	30.189999999999998