The Excel STDEV function returns the standard deviation for data that represents a sample. To calculate the standard deviation for an entire population, use STDEVP or STDEV.P.
- number1 – First number or reference in the sample.
- number2 – [optional] Second number or reference.
The STDEV function calculates the standard deviation in a sample set of data.
Note: STDEV has been replaced with a newer function called STDEV.S, which has identical behavior. Although STDEV still exists for backwards compatibility, Microsoft recommends that people use the newer STDEV.S function instead.
- STDEV calculates standard deviation using the “n-1” method.
- STDEV assumes your data is a sample only. When your data is complete (i.e. when your data representations the entire population), calculate standard deviation using the STDEVP function (or it’s more current replacement, the STDEV.P function).
- Numbers are supplied as arguments. They can be supplied as actual numbers, ranges, arrays, or references that contain numbers.
- The STDEV function will include numbers entered as text and logical values when they are entered directly as arguments. However, when an argument is an array or reference, empty cells, logical values, text, and error values are ignored.
- When you want to include logical values and/or numbers as text in a reference, use the STDEVA function.