Year	% of cohort
1960	58.778273
1961	59.911943
1962	60.004731
1963	59.042914
1964	61.859143
1965	62.896821
1966	64.075788
1967	65.405681
1968	66.152877
1969	66.936621
1970	67.847211
1971	68.791864
1972	68.695797
1973	71.69534
1974	72.439962
1975	74.393875
1976	73.735645
1977	75.966957
1978	76.889018
1979	77.574931
1980	78.508069
1981	80.00307
1982	81.170504
1983	81.525145
1984	82.177376
1985	82.885859
1986	83.657838
1987	83.965961
1988	84.234836
1989	84.183856
1990	84.094868
1991	85.199963
1992	85.763901
1993	85.917497
1994	86.023733
1995	86.159046
1996	86.884567
1997	87.393422
1998	87.433795
1999	87.988151
2000	88.275747
2001	88.041664
2002	88.597316
2003	88.445766
2004	88.867304
2005	89.232287
2006	88.672647
2007	88.380804
2008	88.872413
2009	89.007041
2010	88.982664
2011	89.389386
2012	89.641242
2013	89.828764
2014	90.088231
2015	90.050574
2016	90.256587
2017	90.563266
2018	90.275067
2019	90.448502
2020	89.808639
2021	88.957827
2022	89.50858