Year	% of cohort
1999	90.3152313232422
2000	96.3194122314453
2001	93.9061431884766
2002	92.1175308227539
2003	96.6402969360352
2004	93.5797424316406
2005	91.1574783325195
2006	96.8178787231445
2007	92.5949478149414
2008	95.2516326904297
2010	93.6420974731445
2011	96.0360565185547
2013	97.0781707763672
2015	85.8985900878906
2016	95.8947906494141
2017	87.7592391967773
2018	87.6621017456055
2019	88.0156097412109
2020	88.1936874389648
2021	95.3456726074219