The nth percentile is that value ( or size ) such that n% of values of the whole data lies below it. For example, a score of 7% from the topmost score would be 93 the percentile as it is above 93% of the other scores.
it is used as one of the measure of dispersion.
it is a set of data and is defined as = P90
and P10 are the 90th
and 10th percentile respectively. The semi - percentile range,
i.e. can also be used but it is not common in use.