Year	% of cohort
1971	58.325740814209
1972	74.341682434082
1973	75.3536911010742
1974	77.6134719848633
1982	64.35595703125
1984	70.2567901611328
1985	74.7358016967773
1986	78.6846389770508
1987	83.9501419067383
1988	63.3931617736816
1999	63.341480255127