Year	% of cohort
1970	62.607608795166
1971	62.5041084289551
1972	65.1337890625
1973	64.9226531982422
1974	65.408576965332
1975	66.0298004150391
1976	66.0103302001953
1977	67.5127716064453
1978	67.1478118896484
1979	66.9269104003906
1980	67.1324615478516
1981	66.9711608886719
1982	67.5898590087891
1983	67.9349136352539
1984	68.2689971923828
1985	68.8787231445312
1986	69.5628890991211
1987	69.1064300537109
1988	66.9873199462891
1989	67.8674621582031
1990	69.1622314453125
1991	68.7334365844727
1992	70.0392379760742
1993	70.0201416015625
1994	69.3298416137695
1995	69.6429595947266
1996	69.6324234008789
1997	68.8423004150391
1998	68.1394424438477
1999	69.2373123168945
2000	70.1414489746094
2001	69.0910263061523
2002	68.2849807739258
2003	67.0722885131836
2004	67.6195373535156
2005	68.1932220458984
2006	62.3429718017578
2007	59.3148498535156
2008	64.1158599853516
2009	59.535228729248
2010	59.8354911804199
2011	61.1478118896484
2012	58.0840911865234
2013	57.1722717285156
2014	56.1580009460449
2015	57.1170806884766
2016	57.0592308044434
2017	59.3133888244629
2018	60.9413681030273
2019	62.101001739502
2020	63.9390907287598