Year	% female
1970	33.21251
1971	33.44931
1972	33.72482
1973	34.08376
1974	34.62555
1975	35.50836
1976	35.87446
1977	35.92673
1978	36.2855
1979	36.55221
1980	36.78102
1981	37.11346
1982	37.1625
1983	38.4228
1984	37.85444
1985	38.1477
1986	38.67212
1987	39.00491
1988	39.36793
1989	39.77752
1990	40.15072
1991	40.56342
1992	40.93291
1993	41.24589
1994	41.78522
1995	42.08083
1996	42.409
1997	43.05632
1998	43.71447
1999	44.32034
2000	44.57484
2001	44.78271
2002	45.21326
2003	46.01187
2004	46.01512
2005	46.25632
2006	46.4533
2007	46.7862
2008	47.08864
2009	47.59433
2010	47.71234
2011	47.87843
2012	47.97526
2013	48.58917
2014	48.7241
2015	48.67944
2016	48.82653
2017	48.91638
2018	48.99421