Year	% of cohort
1960	44.348927
1961	45.813874
1962	47.202288
1963	48.437895
1964	49.947547
1965	51.224161
1966	51.88104
1967	53.698196
1968	54.837453
1969	55.848849
1970	53.738339
1971	57.566334
1972	58.802955
1973	59.657549
1974	60.442585
1975	61.302183
1976	62.105412
1977	62.850693
1978	63.545761
1979	64.177772
1980	64.858297
1981	65.61099
1982	66.316141
1983	66.945922
1984	67.552098
1985	68.096249
1986	68.611333
1987	69.132855
1988	69.726023
1989	70.257195
1990	70.757443
1991	71.166197
1992	71.573556
1993	71.945296
1994	72.275907
1995	72.597457
1996	72.911256
1997	73.2003
1998	73.487265
1999	73.848107
2000	74.236019
2001	74.641159
2002	75.015078
2003	75.401585
2004	75.761324
2005	76.038422
2006	76.452185
2007	76.78231
2008	77.093586
2009	77.388044
2010	77.662248
2011	77.933754
2012	78.197989
2013	78.511128
2014	78.939972
2015	79.370333
2016	79.714101
2017	80.153186
2018	80.551531
2019	80.940117
2020	79.485314
2021	77.987393
2022	77.973239