Percentile rank
The
percentile rank of a score is the percentage of scores in its
frequency distribution which are lower. For example, a test score which is greater than 90% of the scores of people taking the test is said to be at the 90th percentile.
Percentile ranks are commonly used to clarify the interpretation of scores on standardized tests. If the distribution is normally distributed, the percentile rank can be inferred from the standard score.