Year	% female
1970	37.12734
1971	37.6153
1972	38.13106
1973	38.72836
1974	39.09554
1975	39.35799
1976	39.62047
1977	40.18479
1978	41.83187
1979	42.04578
1980	42.51449
1981	42.84705
1982	42.87371
1983	42.53239
1984	42.57989
1985	43.02019
1986	43.1494
1987	43.03312
1988	42.35601
1989	43.2576
1990	42.57076
1991	42.87514
1992	43.18211
1993	43.13838
1994	43.31158
1995	43.48993
1996	43.82774
1997	43.8483
1998	43.71888
1999	43.6034
2000	43.87315
2001	44.09599
2002	43.91726
2003	44.46458
2004	44.47211
2005	44.815
2006	45.25229
2007	45.92671
2008	46.03655
2009	46.20758
2010	46.32793
2011	46.71158
2012	47.33629
2013	47.3633
2014	47.3039
2015	47.21372
2016	46.84979
2017	46.95678
2018	46.74869