Year % of cohort 1999 88.7810897827148 2000 94.1888580322266 2006 86.9575424194336 2010 78.0395126342773 2011 92.4111709594727 2014 93.3515930175781 2015 89.8566207885742 2016 93.0722427368164 2017 86.9042663574219 2018 92.7003173828125 2019 92.3006210327148