The percent of cases that are at or below a score.
But we only count half of the cases that are at the score.
Example: in a recent test 12% got D, 50% got C, 30% got B and 8% got A
You got a B, so add up:
• all the 12% that got D,
• all the 50% that got C,
• half of the 30% that got B,
for a total percentile rank of 12%+50%+15% = 77%
In other words you did "as well or better than 77% of the class"
(Why take only half of B? Because you shouldn't imagine you got the "Best B", or the "Worst B", just an average B)
But we only count half of the cases that are at the score.
Example: in a recent test 12% got D, 50% got C, 30% got B and 8% got A
You got a B, so add up:
• all the 12% that got D,
• all the 50% that got C,
• half of the 30% that got B,
for a total percentile rank of 12%+50%+15% = 77%
In other words you did "as well or better than 77% of the class"
(Why take only half of B? Because you shouldn't imagine you got the "Best B", or the "Worst B", just an average B)
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