Year	% of cohort
1971	57.1344604492188
1972	52.8817100524902
1973	58.0639114379883
1974	59.8834800720215
1975	64.8282165527344
1976	65.9447174072266
1977	63.4011917114258
1978	65.1692733764648
1979	67.8392486572266
1980	67.8049163818359
1981	76.454719543457
1982	71.4776992797852
1983	74.6238708496094
1984	73.3609008789062
1986	75.3654708862305
1987	71.7034683227539
1988	69.9198379516602
1989	68.9602890014648
1990	74.4242935180664
1991	70.9445724487305
1994	77.9616394042969
1998	65.349983215332
1999	66.9195404052734
2000	67.6388168334961
2001	63.6906585693359
2002	71.833610534668
2003	74.3822784423828
2004	75.1854095458984
2005	71.4710998535156
2006	79.4375534057617
2007	78.1168365478516
2008	81.9459228515625
2009	73.0402679443359
2011	77.4480361938477
2012	76.7589797973633
2013	75.7479095458984
2014	74.9612579345703
2015	76.7662582397461
2016	73.1396179199219
2017	78.1439895629883
2018	64.9639129638672
2019	63.2160682678223
2020	69.4525680541992
2021	55.0584716796875