Year	% of cohort
1970	53.5764694213867
1971	53.8092613220215
1972	54.2037582397461
1973	54.9403991699219
1974	56.0097389221191
1975	56.2024917602539
1976	56.6093788146973
1977	57.7125511169434
1978	57.2924385070801
1979	56.1515312194824
1980	55.8916015625
1981	55.4025611877441
1982	55.6491508483887
1983	57.4517211914062
1984	58.2553100585938
1985	59.0707015991211
1986	59.8300018310547
1987	58.1318092346191
1988	55.5637588500977
1989	56.0820693969727
1990	56.8306884765625
1991	55.7561416625977
1992	57.7469787597656
1993	56.6272201538086
1994	54.8021583557129
1995	56.4607315063477
1996	54.5237998962402
1997	54.4124488830566
1998	52.8199005126953
1999	56.0651206970215
2000	58.0341911315918
2001	57.5863914489746
2002	57.9632606506348
2003	55.8792304992676
2004	57.782341003418
2005	57.4472312927246
2006	58.3984413146973
2007	57.474681854248
2008	55.699031829834
2009	51.547191619873
2010	51.3805389404297
2011	53.7926406860352
2012	50.1163482666016
2013	48.7264289855957
2014	48.6671905517578
2015	49.788200378418
2016	50.2583084106445
2017	52.1731300354004
2018	54.0302085876465
2019	55.6391181945801
2020	57.4411201477051
2021	57.3452987670898