Year	% of cohort
1971	94.944580078125
1972	94.0535125732422
1973	93.7334594726562
1974	94.5613632202148
1975	92.9807281494141
1976	95.6084823608398
1977	90.1209716796875
1978	91.6550216674805
1979	91.6976699829102
1980	95.4272918701172
1981	97.5923309326172
1983	97.1426010131836
1984	98.6096878051758
1985	97.9225997924805
1989	93.4462966918945
1992	93.2957382202148
1993	96.9202728271484
1994	94.8883972167969
1995	97.2561187744141
1998	77.5508117675781
2005	85.4145431518555
2007	95.5011520385742
2012	98.6966094970703
2015	99.0409622192383
2016	97.1559677124023
2017	97.803581237793
2018	90.0735473632812
2019	95.3459167480469
2020	87.4811706542969
2021	96.146369934082