Year	% of cohort
1983	98.9837188720703
1984	95.6602020263672
1985	96.3593597412109
1986	96.9541397094727
1987	93.2520294189453
1988	98.1323394775391
1989	95.9167633056641
1990	97.1996231079102
1991	97.594970703125
1992	96.9314270019531
1997	98.5660629272461
1998	98.8424606323242
1999	97.8474197387695
2000	97.8330917358398
2001	97.8069686889648
2002	98.522346496582
2003	97.6241912841797
2004	96.2895584106445
2005	98.9699630737305
2006	97.2991561889648
2007	95.921760559082
2008	98.1858520507812
2009	97.0304412841797
2010	97.6518325805664
2011	97.543212890625
2012	97.6111373901367
2013	98.8687591552734
2014	95.571662902832
2015	97.1291809082031
2016	95.5488815307617
2017	97.3735809326172
2018	94.326171875
2019	96.5650405883789
2020	98.3394393920898