Year	% of cohort
1971	56.2594299316406
1972	57.6979293823242
1974	69.4884033203125
1975	66.3383102416992
1976	50.3820381164551
1977	66.9461898803711
1978	50.0813407897949
1979	61.2225685119629
1980	62.9267616271973
1981	57.2514381408691
1982	57.8180389404297
1983	58.6224403381348
1986	62.6615715026855
1987	51.256908416748
1988	66.6846389770508
1995	60.1444892883301
2002	72.3013076782227