Year	% of cohort
1971	54.5742492675781
1972	56.5274887084961
1973	55.6443786621094
1975	58.180248260498
1976	66.1093368530273
1977	62.7946395874023
1978	69.4263763427734
1979	50.7535781860352
1980	47.3536796569824
1982	52.0137901306152
1983	46.1480407714844
1984	48.9522399902344
1985	48.1892395019531
1986	52.8970794677734
1987	50.530891418457
1999	76.8500671386719
2000	88.2187118530273
2001	84.3148498535156
2002	74.8132095336914
2003	86.2878036499023
2004	86.9762802124023
2005	81.2658767700195
2007	84.5281372070312
2008	86.8671188354492
2009	84.0383529663086
2010	87.6494598388672
2011	70.7383804321289
2012	56.5300102233887