Year	% of cohort
1973	40.438720703125
1974	49.9345397949219
1975	35.0167617797852
1976	35.6853408813477
1977	33.8995895385742
1978	36.898250579834
1979	45.4720916748047
1980	36.6412506103516
1981	47.5269012451172
1982	30.1000709533691
1983	33.3819007873535
1984	45.8500518798828
1985	42.1136283874512
1986	56.651969909668
1987	40.649528503418
1988	58.2131004333496
1989	49.832950592041
1990	41.5658493041992
1991	59.2592315673828
1992	31.8529491424561
1993	31.8193492889404
1995	30.1292896270752
1999	38.6421089172363
2001	34.6690406799316
2004	35.463680267334
2005	36.3138389587402
2006	37.02001953125
2007	62.5726509094238
2008	42.1346893310547
2009	52.0753402709961
2010	50.2398300170898
2011	50.581901550293
2012	65.4795074462891
2013	53.5271301269531