Year	% female
1971	25.0142
1972	25.53073
1973	27.39401
1974	29.13913
1975	29.35657
1976	30.65998
1977	30.61238
1978	31.13839
1979	31.79128
1980	34.81417
1981	32.58753
1982	32.0975
1983	32.29054
1984	32.58245
1985	33.03615
1986	32.01398
1987	31.43932
1988	31.64514
1989	32.28662
1990	32.69621
1991	33.23558
1992	33.55151
1993	33.92323
1994	34.08599
1999	36.29822
2000	37.79635
2001	38.04555
2003	39.06395
2004	39.55444
2005	40.03627
2006	40.6336
2007	40.96931
2008	41.41602
2009	41.53619
2010	42.24088
2011	42.85507
2012	43.84704
2013	44.90573
2014	45.79023
2015	47.14562
2016	47.93709
2017	48.54717
2018	49.29677