Year	% of cohort
1991	97.1540298461914
1992	96.3476486206055
1993	95.9360504150391
1994	96.6138610839844
1995	96.4788208007812
1996	96.1285018920898
1997	95.8110961914062
1998	95.9015426635742
1999	95.8232421875
2000	96.4234313964844
2001	96.5545196533203
2002	96.8137893676758
2003	96.6250991821289
2004	97.1204071044922
2005	97.6648635864258
2006	97.6162567138672
2007	96.7780227661133
2008	96.4196701049805
2009	98.6300582885742
2010	97.0373229980469
2011	95.6332015991211
2012	96.1345596313477
2013	97.1366729736328
2014	93.8497772216797
2015	97.4748687744141
2016	98.818962097168
2017	99.0255966186523
2018	98.9771881103516
2019	98.682991027832
2020	98.657829284668
2021	98.6618728637695