Year	% female
1971	17.22212
1972	20.38105
1973	22.73151
1974	24.92292
1975	27.05254
1976	30.93831
1977	33.76444
1978	36.32547
1979	37.9053
1980	38.93166
1981	38.75735
1983	40.51348
1986	45.12248
2002	49.78156
2003	49.76111