Standard deviation is a measure of how much variance there is in a set of numbers compared to the average (mean) of the numbers. The STDEVPA function is meant to estimate standard deviation for an entire population. If data represents a sample, use the STDEVA function. In the example shown, the formula in E5 is:

Standard Deviation functions in Excel

The table below summarizes the standard deviation functions provided by Excel. Notes:

Only use STDEVPA when you need to evaluate logicals or text in the standard deviation calculation. STDEVPA calculates standard deviation using the “n” method. STDEVA assumes data is an entire population. When data representations a sample, use STDEVA or STDEV.S Numbers are supplied as arguments. They can be supplied as actual numbers, ranges, arrays, or references that contain numbers. STDEVPA will evaluate logical values and/or numbers in supplied references. To ignore these values use STDEVP or STDEV.P

Dave Bruns

Hi - I’m Dave Bruns, and I run Exceljet with my wife, Lisa. Our goal is to help you work faster in Excel. We create short videos, and clear examples of formulas, functions, pivot tables, conditional formatting, and charts.