Year	% of cohort
1971	96.1851501464844
1972	88.9720001220703
1973	94.2537994384766
1974	94.3927764892578
1975	92.3254165649414
1976	94.9147491455078
1977	89.6643676757812
1978	94.1248474121094
1979	91.7076416015625
1980	93.2131576538086
1983	95.1621398925781
1984	98.8582992553711
1989	94.1347122192383
1992	95.4697418212891
1993	99.8573989868164
1994	98.4526596069336
1995	99.4150314331055
2005	85.4819488525391
2007	98.9380493164062
2012	98.1033935546875
2015	98.9838104248047
2016	96.2299423217773
2017	98.5733032226562
2018	89.6614303588867
2019	95.9401702880859
2020	87.6590118408203
2021	95.5340805053711