Year	% of cohort
1970	54.9738883972168
1971	56.1061096191406
1972	56.3853302001953
1973	58.7300300598145
1974	59.0312690734863
1975	56.9674415588379
1976	57.6759605407715
1977	58.611011505127
1978	57.1566696166992
1979	57.667911529541
1980	56.8880004882812
1981	56.4674797058105
1982	58.0139694213867
1983	58.6831092834473
1984	58.4662208557129
1985	60.0777397155762
1986	59.9546394348145
1987	58.6358299255371
1988	57.1854591369629
1989	57.768928527832
1990	57.8980293273926
1991	57.839168548584
1992	59.6652297973633
1993	58.182071685791
1994	56.416561126709
1995	57.2099685668945
1996	54.7213897705078
1997	54.1492614746094
1998	54.1207313537598
1999	53.9192581176758
2000	56.2272682189941
2001	59.5479011535645
2002	59.1281394958496
2003	56.0673408508301
2004	58.961498260498
2005	58.3649597167969
2006	59.5156402587891
2007	58.0782814025879
2008	55.4993705749512
2009	53.0580902099609
2010	51.6381187438965
2011	54.0385589599609
2012	51.8221893310547
2013	51.0177803039551
2014	51.502311706543
2015	53.5318298339844
2016	54.7327308654785
2017	56.04833984375
2018	57.0727806091309
2019	57.6658592224121
2020	59.1609992980957