Year	% female
1970	34.54454
1971	34.49548
1972	34.76235
1973	35.08336
1974	35.5648
1975	35.42233
1976	35.98882
1977	36.44633
1978	36.75589
1979	37.16134
1980	37.40126
1981	38.06019
1982	38.59533
1983	39.13945
1984	39.54303
1985	39.92689
1986	40.3317
1987	40.72269
1988	41.21046
1989	41.60103
1990	42.20231
1991	42.72759
1992	43.39376
1993	43.68444
1994	43.68522
1995	44.3553
1996	44.52729
1997	45.00744
1998	45.51702
1999	46.0552
2000	46.36702
2001	46.53072
2002	46.97585
2003	47.22916
2004	47.41423
2005	47.67874
2006	47.85505
2007	47.93864
2008	47.99428
2009	47.89419
2010	47.89499
2011	48.00858
2012	48.04139
2013	48.02681
2014	47.83626
2015	47.9989
2016	48.05563
2017	48.13987
2018	48.24162