Year % of cohort 1974 91.3307189941406 1980 74.7453918457031 1981 76.5216674804688 2010 84.3138580322266 2011 70.3949890136719 2012 82.6672668457031 2013 83.2831115722656 2014 77.4063186645508 2015 86.006462097168 2016 78.3862686157227 2017 66.6751937866211 2018 81.9692230224609