Year	% of cohort
2001	99.1832885742188
2002	99.1036224365234
2003	99.2717590332031
2004	99.5188217163086
2005	99.3248825073242
2006	99.0034103393555
2007	99.1369094848633
2008	98.9600677490234
2009	98.9625396728516
2010	98.9286804199219
2011	99.0322723388672
2012	99.1751022338867
2013	99.2633819580078
2014	98.8958129882812
2015	99.279167175293
2016	98.7972869873047
2017	99.0707168579102
2018	99.0317993164062
2019	99.1061172485352
2020	98.8156433105469