Year	% of cohort
1993	99.4683074951172
1994	100
1995	98.4723968505859
1996	99.0602035522461
1997	98.4147186279297
1998	99.0234527587891
1999	99.6803207397461
2001	98.3755416870117
2002	98.7922897338867
2008	99.5137176513672
2009	98.9923400878906
2010	98.5942916870117
2011	98.8252868652344
2012	99.6113815307617
2013	99.0477294921875
2014	98.5826416015625
2015	98.9360961914062
2016	99.4162368774414
2017	99.2074890136719
2018	99.7261962890625
2019	99.563102722168
2020	99.3664321899414
2021	99.7394866943359