Year	% female
1970	39.98819
1971	39.93735
1972	39.45379
1973	40.30903
1974	42.82735
1975	39.93816
1976	41.81726
1977	41.52724
1978	45.03203
1979	48.51257
1980	52.31482
1981	51.06037
1982	46.32391
1983	43.28144
1984	43.55874
1985	45.58074
1986	47.04129
1987	47.40959
1988	48.81017
1989	48.12845
1990	49.99828
1991	48.04434
1992	49.58755
1993	51.52291
1994	50.66541
1995	50.07668
1996	49.33958
1997	49.58103
1998	47.56335
1999	47.18982
2000	46.26108
2001	46.22526
2002	49.74216
2003	49.02164
2004	47.9154
2005	47.8335
2006	45.97719
2007	45.17888
2008	47.21084
2009	46.02996
2010	46.86475
2011	49.69292
2012	48.34528
2013	47.38798
2014	47.56588
2015	44.73063
2016	45.26749
2017	45.28997
2018	45.37166