The Excel STDEVA function calculates standard deviation for a sample of data. Unlike the STDEV function, STDEVA will evaluate text and logicals that appear in references. To calculate standard deviation for an entire population, use STDEVPA or STDEV.P.
Get standard deviation in a sample
Estimated standard deviation
=STDEVA (number1, [number2], ...)
number1 - First number or reference in the sample.
The STDEVA function calculates the standard deviation for a sample set of data, evaluating text and logicals as numbers as part of the calculation. TEXT is evaluated as zero, TRUE is evaluated as 1, and FALSE is evaluated as zero.
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 STDEVA function is meant to estimate standard deviation in a sample. If data represents an entire population, use the STDEVPA function.