Year	% of cohort
1971	54.1739692687988
1972	54.6973609924316
1973	57.3793296813965
1974	57.434871673584
1975	55.5789184570312
1976	56.8400688171387
1977	57.5133781433105
1978	56.0991706848145
1979	56.5589790344238
1980	55.6972808837891
1981	54.8564109802246
1982	56.5959815979004
1983	56.3144798278809
1984	56.0182685852051
1985	57.7046508789062
1986	57.4462699890137
1987	56.5878601074219
1988	56.280689239502
1989	56.8456916809082
1990	57.3099899291992
1991	56.8440208435059
1992	58.463939666748
1993	56.4387588500977
1994	54.9769515991211
1995	55.3173408508301
1996	53.2583694458008
1997	53.0657806396484
1998	53.569709777832
1999	52.8263893127441
2000	55.397518157959
2001	58.2971801757812
2002	57.3474197387695
2003	54.9709014892578
2004	58.1138610839844
2005	58.4154396057129
2006	58.8187789916992
2007	58.0382499694824
2008	56.1205291748047
2009	53.3060302734375
2010	51.7980690002441
2011	54.7482986450195
2012	53.1475410461426
2013	53.9668807983398
2014	55.1503105163574
2015	57.3255310058594
2016	57.9976692199707
2017	57.8630485534668
2018	59.3398590087891
2019	59.3805999755859
2020	60.3121910095215