Year	% of cohort
1960	62.225625
1961	63.044313
1962	63.107334
1963	63.301134
1964	64.171679
1965	64.270492
1966	64.464323
1967	65.194989
1968	65.316515
1969	65.481772
1970	65.603923
1971	65.647355
1972	65.844726
1973	66.507251
1974	66.558481
1975	36.962879
1976	6.596451
1977	46.612496
1978	46.647972
1979	46.66622
1980	47.223675
1981	47.381169
1982	19.362126
1983	42.049523
1984	42.383134
1985	42.640991
1986	43.469771
1987	49.718345
1988	50.449687
1989	48.81524
1990	49.533439
1991	73.30903
1992	73.263745
1993	73.207808
1994	73.842916
1995	75.153364
1996	75.359155
1997	75.74353
1998	76.066022
1999	77.264721
2000	77.952121
2001	78.500433
2002	79.233626
2003	80.542147
2004	80.978297
2005	81.488862
2006	79.143817
2007	82.314403
2008	83.649377
2009	84.193566
2010	84.68258
2011	85.101744
2012	85.487619
2013	85.628429
2014	85.897265
2015	86.290768
2016	86.65564
2017	86.736697
2018	87.121362
2019	86.321664
2020	83.85315
2021	78.751893
2022	77.598732