Year	% of cohort
1971	57.6329917907715
1972	57.7228698730469
1973	59.8228492736816
1974	60.3149299621582
1975	58.0923004150391
1976	58.354850769043
1977	59.5040702819824
1978	58.037769317627
1979	58.6031684875488
1980	57.9000015258789
1981	57.8458213806152
1982	59.227481842041
1983	60.7208518981934
1984	60.5685005187988
1985	62.11962890625
1986	62.1675491333008
1987	60.4008407592773
1988	57.9756011962891
1989	58.577320098877
1990	58.4132995605469
1991	58.7120513916016
1992	60.7219581604004
1993	59.6737785339355
1994	57.6502304077148
1995	58.8158798217773
1996	55.9981384277344
1997	55.0973014831543
1998	54.6159896850586
1999	54.9053802490234
2000	56.9774894714355
2001	60.6804084777832
2002	60.7408103942871
2003	57.0752182006836
2004	59.7439804077148
2005	58.3182983398438
2006	60.1562194824219
2007	58.1150817871094
2008	54.9217491149902
2009	52.8290405273438
2010	51.4936103820801
2011	53.3900108337402
2012	50.609001159668
2013	48.3354415893555
2014	48.2419891357422
2015	50.1159515380859
2016	51.7974586486816
2017	54.4085311889648
2018	55.0133209228516
2019	56.102409362793
2020	58.1070899963379