Year	% of cohort
1971	63.9046287536621
1972	63.6877403259277
1973	64.7821884155273
1974	66.1014709472656
1975	65.1997299194336
1976	65.3987121582031
1977	66.2986526489258
1978	65.5940704345703
1979	65.9114685058594
1980	65.7947692871094
1981	66.0878067016602
1982	67.0144805908203
1983	67.2081298828125
1984	67.2162017822266
1985	67.6114730834961
1986	68.0569229125977
1987	67.0860137939453
1988	65.3319396972656
1989	65.6432571411133
1990	66.0636672973633
1991	65.488166809082
1992	67.0820999145508
1993	66.4579391479492
1994	64.768913269043
1995	65.3487930297852
1996	63.6114616394043
1997	63.0870704650879
1998	63.1360282897949
1999	63.2758598327637
2000	64.8578186035156
2001	66.681037902832
2002	64.8935623168945
2003	62.1494598388672
2004	62.8209609985352
2005	62.2817497253418
2006	58.860481262207
2007	57.4881706237793
2008	60.5539283752441
2009	56.158031463623
2010	55.5476303100586
2011	57.0220985412598
2012	54.9478912353516
2013	53.5257110595703
2014	53.5208015441895
2015	54.2696304321289
2016	54.5298690795898
2017	56.7555885314941
2018	57.4268989562988
2019	58.3291015625
2020	59.7265281677246