The STDEV.S function is meant to estimate standard deviation in a sample.
If data represents an entire population, use the STDEV.P function.
Note: STDEV.S replaces the older STDEV function, but has identical behavior.
Although STDEV still exists for backwards compatibility, Microsoft recommends that people use the newer STDEV.S function instead.
Standard Deviation functions in Excel
The table below summarizes the standard deviation functions provided by Excel.
To calculate the standard deviation for an entire population, use STDEVP or STDEV.P.
STDEVP Function
The STDEVP function calculates the standard deviation for data that represents a population.
STDEVP has been replaced with a newer function called STDEV.P, which has the same behavior.
STDEV.P Function
The Excel STDEV.P function calculates the standard deviation for a sample set of data.
STDEV.P calculates standard deviation using the “n” method, ignoring logical values and text.
