Percentiles

The percentile is a concept often used to summarize data and place the score or measurement taken on an individual into the context of a larger population. For any particular number p between 0 and 100, the pth percentile of a set of n measurements arranged in order of magnitude is the value that has at most p% of the observations below it and at most (100 − p)% above it. Roughly speaking, the first percentile is the number that divides the bottom 1% of the data from the top 99%; the second percentile is the number that divides the bottom 2% of the data from the top 98%; and so on. Therefore, if a man has a body mass index score at the 98th ...