Year	% of cohort
1971	98.1350173950195
1972	96.7603988647461
1973	96.239013671875
1974	97.4816665649414
1975	99.0224533081055
1976	99.4242630004883
1978	98.8303298950195
1979	99.2302932739258
1980	98.8618774414062
1981	98.2086791992188
1982	98.3112869262695
1983	98.6189727783203
1987	99.1077423095703
1988	99.4397583007812
1989	99.7029724121094
1990	99.5470275878906
1991	99.7127075195312
1999	98.3300476074219
2000	99.257080078125
2001	98.7473526000977
2002	98.8593826293945
2003	98.8291168212891
2004	99.0023498535156
2005	98.9174118041992
2006	99.2819290161133
2007	99.6493606567383
2008	99.0153198242188
2009	99.4213409423828
2010	95.5790405273438
2012	99.7207336425781
2013	99.5562362670898
2018	99.6781005859375
2019	99.7029266357422
2020	99.8131713867188
2021	99.8223876953125