>>Now, ianr you have clarified your question I can try to answer it. It means the percentage of the year 13 cohort who gained A or A* in the exam subjects that they took. So if 100 students took (say) 350 A level subject exams between them, then in the case of Alleyns, 77.4% of those results were A/A*. If James was taking geography, history and english, and gained an A or A* in all three then he would have scored 100%. If Mary was taking French, Biology and Economics and gained A, B C respectively then her score would have been 33.3%.