Year	% of cohort
1991	98.637336730957
1992	92.1746063232422
1993	97.441291809082
1994	97.0539703369141
1995	96.8584289550781
1996	96.7844314575195
1998	97.1715698242188
1999	97.6447830200195
2000	97.886833190918
2001	98.8647994995117
2002	97.1289215087891
2003	97.7822189331055
2004	97.9548187255859
2005	97.632698059082
2006	98.0050811767578
2007	98.0237731933594
2008	97.8572006225586
2009	98.3541412353516
2010	98.3820495605469
2011	97.6839904785156
2012	98.2634811401367
2013	98.4128723144531
2014	99.2758483886719
2015	98.6006927490234
2016	98.9827117919922
2017	98.8503494262695
2018	98.3041915893555
2019	99.3387908935547
2020	99.429069519043
2021	99.404052734375