Year	% of cohort
1971	56.6911010742188
1972	56.948070526123
1973	57.4878692626953
1974	58.5314788818359
1975	58.4872817993164
1976	58.4814186096191
1977	59.8830718994141
1978	59.6518707275391
1979	58.5443687438965
1980	58.4605293273926
1981	58.2130813598633
1982	58.6007385253906
1983	60.8173217773438
1984	61.787899017334
1985	62.7007713317871
1986	63.7672309875488
1987	61.6713409423828
1988	58.0650787353516
1989	58.6212882995605
1990	59.2787094116211
1991	58.2985687255859
1992	60.3349990844727
1993	59.7987289428711
1994	57.5835914611816
1995	59.5642395019531
1996	57.1824913024902
1997	56.4765396118164
1998	54.5419387817383
1999	57.6764183044434
2000	59.8108100891113
2001	59.9977798461914
2002	60.6880798339844
2003	57.8217811584473
2004	59.1089515686035
2005	58.1109313964844
2006	59.6149787902832
2007	58.1092796325684
2008	55.8836288452148
2009	52.0348701477051
2010	52.3553695678711
2011	54.2426910400391
2012	50.1047401428223
2013	47.10791015625
2014	46.4200706481934
2015	47.3312911987305
2016	47.973258972168
2017	51.0265083312988
2018	52.4516983032227
2019	54.4794311523438
2020	56.8828811645508
2021	56.8484382629395