Year	% of cohort
1972	90.4789962768555
1973	89.2524185180664
1975	82.9316177368164
1976	99.7337036132812
1977	95.1773071289062
1978	96.6545791625977
1979	90.4569778442383
1980	90.436637878418
1982	85.5807800292969
1983	76.5313415527344
1984	73.1431579589844
1985	76.2216110229492
1986	79.7214736938477
1987	80.649528503418
1988	84.1874694824219
1989	78.6691818237305
1990	71.9119415283203
1991	75.0220108032227
1992	64.5558319091797
1993	85.6821365356445
1994	76.9576568603516
1995	76.351676940918
1996	74.8199615478516
1997	70.7841186523438
1999	72.5460433959961
2000	89.7093276977539
2006	83.3722381591797
2008	66.0408096313477
2011	84.3472366333008
2012	78.9480514526367
2013	78.2085494995117
2014	85.1222381591797
2015	83.047492980957
2019	78.9803466796875
2020	73.5793914794922
2021	66.3007278442383