Year	% of cohort
1970	65.7052612304688
1971	76.5507888793945
1972	75.9761962890625
1973	75.5195922851562
1974	71.5160064697266
1975	69.5351791381836
1976	73.0993118286133
1977	69.7712020874023
1978	71.0934829711914
1979	72.6802215576172
1980	76.5655364990234
1981	69.4488983154297
1982	73.1031112670898
1983	74.4639129638672
1984	74.9118423461914
1985	70.4798431396484
1986	77.2862014770508
1987	75.8986892700195
1988	71.8100814819336
1989	77.1564483642578
1990	74.2771835327148
1991	73.9359130859375
1992	74.2173309326172
1993	75.9581832885742
1994	84.5544281005859
1995	72.6958465576172
1996	72.7946166992188
1997	77.6469421386719
1998	81.2472763061523
1999	72.2688293457031
2000	69.0740432739258
2001	77.3200988769531
2002	73.990837097168
2004	81.3878631591797
2005	91.2599105834961
2006	74.9475326538086
2009	95.0840377807617
2012	88.0237274169922
2013	92.554069519043
2014	92.1758499145508
2015	91.7720413208008
2016	95.12744140625
2018	96.6127624511719