Year	% of cohort
2009	95.9930572509766
2011	94.0715408325195
2012	95.698486328125
2015	96.0771331787109
2016	92.2715835571289
2017	92.7654495239258
2018	88.5445327758789
2019	93.9547424316406
2020	85.7431411743164