Year	% of cohort
1973	55.7949714660645
1974	56.2870903015137
1975	55.7628517150879
1976	55.908561706543
1977	57.1724395751953
1978	57.2880096435547
1979	58.0626983642578
1980	58.1383399963379
1981	58.4576988220215
1982	58.8331604003906
1983	59.4322319030762
1984	59.9410095214844
1985	60.7834815979004
1986	61.6864013671875
1987	62.1200904846191
1988	62.1061706542969
1989	62.2846603393555
1990	62.9656982421875
1991	62.9098701477051
1992	64.0808715820312
1993	64.0551834106445
1994	63.3434410095215
1995	64.0093383789062
1996	63.3401718139648
1997	63.3516883850098
1998	63.4856109619141
1999	64.4396820068359
2000	65.4430465698242
2001	66.9621200561523
2002	66.1959686279297
2003	64.8642501831055
2004	64.932487487793
2005	64.5237884521484
2006	62.29248046875
2007	61.4396705627441
2008	63.4744300842285
2009	60.4179000854492
2010	58.9894599914551
2011	60.7476501464844
2012	58.7502593994141
2013	60.0870208740234
2014	60.2156600952148
2015	60.9509506225586
2016	60.5844688415527
2017	62.1873817443848
2018	60.7417488098145
2019	61.4097709655762
2020	62.5678787231445