Percentile
The value below which a given percentage of the data falls.
A percentile is a value below which a certain percentage of observations in a dataset fall. The 25th percentile (first quartile) is the value below which a quarter of the data lies; the 50th percentile is the median. Percentiles describe relative standing — a test score in the 90th percentile means it's higher than 90% of scores — and are computed by ranking the data and interpolating to the requested position.