Year	% of cohort
1960	51.549713
1961	52.049254
1962	52.28022
1963	52.781067
1964	53.318614
1965	53.897897
1966	54.481439
1967	54.95772
1968	55.6505
1969	56.063548
1970	56.586189
1971	56.963525
1972	57.425305
1973	57.474712
1974	58.480482
1975	58.833884
1976	60.476823
1977	60.222496
1978	58.973221
1979	58.703084
1980	59.162495
1981	59.588122
1982	61.298663
1983	63.203788
1984	63.038547
1985	62.538496
1986	62.655784
1987	62.044057
1988	62.58815
1989	63.565855
1990	64.428111
1991	62.103247
1992	65.315928
1993	65.082286
1994	65.484341
1995	65.069201
1996	64.910457
1997	65.37072
1998	66.355851
1999	67.062679
2000	67.517832
2001	67.441661
2002	67.650796
2003	67.903451
2004	68.087365
2005	68.451955
2006	68.444431
2007	68.256868
2008	67.969179
2009	67.379619
2010	67.635532
2011	67.531389
2012	67.774724
2013	67.950532
2014	68.434614
2015	68.000032
2016	68.430325
2017	68.372979
2018	68.749512
2019	66.493093
2020	66.921059
2021	65.068436
2022	69.699465