Year	% of cohort
1996	90.775146484375
1997	90.8272476196289
1998	90.6382904052734
1999	90.8523406982422
2000	90.8119735717773
2001	90.8521270751953
2002	90.7842788696289
2003	90.7231521606445
2004	90.7091598510742
2005	90.5307769775391
2006	90.6388626098633
2007	90.4984893798828
2008	90.8634033203125
2009	90.8220062255859
2010	90.7851104736328
2011	90.684928894043
2012	90.6522827148438
2013	90.8027267456055
2014	90.7721405029297
2015	90.8030700683594
2016	90.8109664916992
2017	90.7966690063477
2018	90.8059005737305
2019	90.7984237670898
2020	87.8491363525391
2021	87.8383331298828