Year	% of cohort
1996	91.1808929443359
1997	91.171257019043
1998	91.1596298217773
1999	91.2551193237305
2000	91.2499008178711
2001	91.2447280883789
2002	91.2304611206055
2003	91.2115478515625
2004	91.1907501220703
2005	91.1859664916992
2006	91.1692428588867
2007	91.1521377563477
2008	91.1765975952148
2009	91.1869583129883
2010	91.189208984375
2011	91.2007369995117
2012	91.2208633422852
2013	91.2290115356445
2014	91.2427520751953
2015	91.2655792236328
2016	91.2688217163086
2017	91.290397644043
2018	91.3019714355469
2019	91.3070068359375
2020	88.2005767822266
2021	88.1896133422852