Year	% of cohort
1972	92.1805572509766
1973	91.2964401245117
1974	88.8582763671875
1975	90.5622711181641
1976	86.712532043457
1977	87.9362335205078
1978	87.0466918945312
1979	90.0972213745117
1980	88.4216613769531
1981	89.6918029785156
1982	91.7732696533203
1983	92.6986465454102
1984	94.8645324707031
1985	96.3120269775391
1986	95.2204132080078
1987	95.2038116455078
1988	93.1729583740234
1989	95.0960464477539
1990	95.5558090209961
1991	94.4603271484375
1992	92.434700012207
1993	93.2778167724609
1994	93.1705169677734
1995	94.2223205566406
1996	93.4541931152344
1998	94.3955688476562
1999	93.9685287475586
2000	96.8082275390625
2001	94.8035125732422
2002	96.5017013549805
2003	95.0625686645508
2004	94.211181640625
2005	94.7521896362305
2006	94.5844573974609
2007	94.6105499267578
2009	93.155158996582
2010	94.0105514526367
2011	91.1180191040039
2012	94.8486785888672
2013	92.3475570678711
2014	93.0100326538086
2015	93.1571197509766
2016	93.7827911376953
2017	95.3304595947266
2018	91.2359771728516
2020	90.1042633056641
2021	91.9202423095703