Year	% of cohort
1971	97.8063430786133
1972	97.6276397705078
1973	98.6358413696289
1981	99.1472015380859
1982	98.7028427124023
1983	99.0473403930664
1984	99.5788726806641
1985	96.912956237793
1986	99.6775588989258
1987	98.6770706176758
1988	98.9358291625977
1989	98.1697311401367
1990	98.9468765258789
1991	93.2916793823242
1992	99.9609375
1998	99.7713012695312
1999	99.8757629394531
2000	99.9356536865234
2004	91.2135391235352
2007	98.775032043457
2008	99.5116500854492
2009	99.1679916381836
2012	98.8132934570312
2013	99.4870376586914
2014	99.9362716674805
2017	99.8143692016602
2018	99.8168563842773
2019	99.8524017333984
2020	99.7070693969727
2021	99.3080215454102