Year	% of cohort
1973	55.9556617736816
1974	56.3239593505859
1975	56.551139831543
1976	57.0266304016113
1977	58.0322685241699
1978	58.144458770752
1979	59.0606117248535
1980	58.2134017944336
1981	58.3755683898926
1982	60.1263694763184
1983	59.9083518981934
1984	60.5835418701172
1985	61.4429817199707
1986	62.3252296447754
1987	62.8117599487305
1988	63.4933204650879
1989	63.4827308654785
1990	64.2277679443359
1991	63.9567718505859
1992	64.7728729248047
1993	64.4400177001953
1994	63.7762908935547
1995	64.2078018188477
1996	63.3145294189453
1997	63.6922187805176
1998	64.0331726074219
1999	64.7106704711914
2000	65.5624008178711
2001	66.4018707275391
2002	65.551399230957
2003	64.3023834228516
2004	64.898078918457
2005	65.4437026977539
2006	61.8948097229004
2007	60.872688293457
2008	63.1503410339355
2009	61.1413917541504
2010	59.7016296386719
2011	62.2890396118164
2012	60.4010314941406
2013	62.3734817504883
2014	63.4202690124512
2015	64.4714279174805
2016	63.636848449707
2017	63.9979209899902
2018	65.1281585693359
2019	65.49072265625
2020	66.1648635864258