Year	% of cohort
1960	31.321487
1961	31.88915
1962	32.666831
1963	33.296705
1964	34.067942
1965	34.602838
1966	35.313395
1967	36.109456
1968	36.615763
1969	37.446181
1970	38.343042
1971	39.141727
1972	39.975266
1973	41.20498
1974	42.83614
1975	44.047625
1976	45.894356
1977	47.350534
1978	48.778125
1979	50.047167
1980	51.034386
1981	52.045734
1982	52.080494
1983	52.37779
1984	51.212923
1985	51.220438
1986	51.231919
1987	51.185548
1988	50.596301
1989	50.185756
1990	49.644491
1991	49.01553
1992	48.586299
1993	48.014644
1994	47.59585
1995	47.224957
1996	46.73348
1997	45.478731
1998	43.70806
1999	42.197589
2000	41.361323
2001	40.642521
2002	40.139982
2003	39.968018
2004	40.016165
2005	40.276642
2006	40.962428
2007	42.111201
2008	43.434786
2009	44.91253
2010	45.925416
2011	46.846343
2012	47.830546
2013	49.057247
2014	49.185529
2015	50.452841
2016	50.416794
2017	51.684162
2018	51.690427
2019	52.972018
2020	52.187348
2021	51.003362
2022	51.815062