Year	% of cohort
1971	42.7726402282715
1972	29.4929599761963
1974	41.5891990661621
1988	34.46630859375
1989	32.8607788085938
1990	39.3990592956543
1991	21.7599506378174
1992	31.4063701629639
1993	28.1224308013916
1994	27.7338008880615
1995	40.7597503662109
1998	37.718921661377
1999	52.4225311279297
2000	36.1403388977051
2001	34.6823883056641
2002	55.409610748291
2003	59.862419128418
2004	42.8821983337402
2005	35.9786491394043
2006	42.4667015075684
2007	42.6606216430664
2008	49.3871917724609
2009	34.5846900939941
2010	39.5192985534668
2011	40.6585693359375
2012	37.969799041748
2013	40.0512199401855
2014	42.5731391906738
2015	35.1020584106445
2018	31.569299697876