The percentiles generally are demonstrated as P(m), where m is the number taking values between 0 and 100.

Intuitively, the P(m) percentile of a set of n measurements, arranged in order of magnitude, is the value such m percent of the measurements are less than or equal to that corresponding value.

Some of the specific percentiles frequently used as variability measures are 25th, 50th, and 75th percentiles.

Various methods may be used for the calculation of percentiles.

In order to calculate the percentiles, the sample measurements must be sorted from largest to smallest.