when did o level grades change from numbers to letters
GCE Ordinary Level (United Kingdom) Initially candidates were only awarded a pass or fail classification, though the independent exam boards soon offered competing numeric and alphabetic classifications, for example 1, 2, 3, 4, 5 and 6 would be a pass, while grades 7, 8 and 9 were fails from the JMB. From 1975 standardized alphabetic grades where introduced with grades A, B, C, D, and E were passes, and f and U (Unclassified) were fails.[4][5] Between 1965 and 1985 grades were allocated primarily on a norm-referenced basis, assigning a fixed proportion of each cohort to each grade (A 10%, B 15%, C 25-30%, D 5-10%, E 5-10%, U 15-20%).[6][7] Though some exceptions existed, both at the subject and Exam Board level, with Latin and Greek pass rates being consistently higher than other subjects, with 75.4% passing in 1976, in contrast to an average 59% pass rate across all subjects e.g. Biology 56.4%, History 57%. The pass rate and top awards by the Oxford & Cambridge board were also consistently higher than the other boards e.g. In 1976, 27% of Latin entrants gained an A, and ~17% of French, German and Music candidates, this was attributed to the O&C board being primarily used by the Independent schools.[6] The proportion obtaining a pass, A-D, or equivalent was initially fixed at 57% - 58%, and remained under 60% through the 1970s, though there was regional variation with Northern Ireland awarding consistently more pass grades than Wales e.g. In 1982, the pass rates were: Northern Ireland 62%, England 58% Wales 53%.[6] In 1984 a decision was taken, by the Secondary Examinations Council, to replace the norm referencing with criteria referencing, where 16+ and 18+ grades would in future be awarded on Examiner Judgement,[8] this change was implemented, at O-Level, in June 1986. In the final year DES statistics were available 6.8% achieved an A, and 39.8% an A-C grade.