Year	% female
1972	33.33953
1973	28.73471
1974	29.22386
1975	28.48553
1976	28.60545
1977	28.48099
1978	28.29689
1979	29.38319
1980	30.70212
1981	29.36475
1982	30.25318
1983	31.1553
1984	31.57826
1985	32.71199
1986	33.64289
1987	34.49695
1988	35.74443
1989	35.93594
1990	36.67955
1991	37.76337
1993	37.52195
1994	39.63636
1995	40.53524
1996	40.47519
1999	41.22648
2000	42.8145
2001	43.5976
2002	43.60331
2004	44.57286
2005	44.71307
2006	45.48294
2007	45.22712
2008	45.60602
2009	46.37104
2010	47.28104
2011	47.41079
2012	46.96703
2013	47.23515
2014	47.46204
2015	47.7728
2016	47.0801
2017	48.41682
2018	49.53251