Year	% female
1970	27.91821
1971	27.94613
1972	28.34014
1973	28.74049
1974	29.16903
1975	29.61611
1976	29.7475
1977	29.80566
1978	30.04494
1979	30.35083
1980	30.72379
1981	31.05984
1982	31.17428
1983	33.27619
1984	32.18332
1985	32.56013
1986	33.26737
1987	33.53054
1988	34.04124
1989	34.56396
1990	35.02791
1991	35.68787
1992	36.26604
1993	36.86622
1994	37.52104
1995	37.75359
1996	38.14046
1997	38.95087
1998	39.74454
1999	40.47149
2000	40.79577
2001	41.14869
2002	41.94101
2003	43.47914
2004	43.21182
2005	43.69514
2006	43.89354
2007	44.36852
2008	44.92835
2009	45.67242
2010	45.8277
2011	46.1543
2012	46.23951
2013	47.25645
2014	47.49713
2015	47.49095
2016	47.57811
2017	47.54081
2018	47.60807
