Year	% of cohort
1971	99.1674194335938
1972	97.5792388916016
1973	96.9463577270508
1974	98.5665817260742
1975	99.7488174438477
1976	99.8091125488281
1977	99.7452697753906
1978	98.5949401855469
1979	99.6800918579102
1980	99.3699264526367
1981	98.4763565063477
1982	98.8323669433594
1983	98.831787109375
1987	99.6128616333008
1988	99.7367401123047
1989	99.8290481567383
1990	100
1991	99.9243087768555
1999	98.3252182006836
2000	99.704948425293
2001	98.8978881835938
2002	98.8613433837891
2003	99.4461898803711
2004	99.0796432495117
2005	99.4527969360352
2006	99.4182281494141
2007	99.887092590332
2008	99.2806396484375
2009	99.7886581420898
2010	96.6547393798828
2012	99.9648284912109
2013	99.7051010131836
2017	100
2018	100
2019	100
2020	99.7635192871094
2021	99.9085388183594