PROC HPBIN computes the 0% (minimum), 1%, 5%, 10%, 25%, 50%, 75%, 90%, 95%, 99%, and 100% (maximum) percentiles of each binning variable.
Let be the number of nonmissing values for a variable, and let , , ..., represent the ordered values of the variable. Let the th percentile be , set , and let = + , where is the integer part of and is the fractional part of . Then the th percentile is as described as:
Note: To avoid the time-consuming sorting process, the HPBIN procedure uses an iterative projection method to compute percentiles according to the preceding formula.