Estimates standard deviation based on a sample. The standard deviation is a measure of how widely values are dispersed from the average value (the mean).

## Syntax

STDEV(number1,number2,...)

Number1,number2,...     are 1 to 30 number arguments corresponding to a sample of a population.

## Remarks

• Logical values such as TRUE and FALSE and text are ignored. If logical values and text must not be ignored, use the STDEVA function.

• STDEV assumes that its arguments are a sample of the population. If your data represents the entire population, then compute the standard deviation using STDEVP.

• The standard deviation is calculated using the "nonbiased" or "n-1" method.

• STDEV uses the following formula:

## Example

Suppose 10 tools stamped from the same machine during a production run are collected as a random sample and measured for breaking strength.

 St1 St2 St3 St4 St5 St6 St7 St8 St9 St10 Formula Description (Result) 1345 1301 1368 1322 1310 1370 1318 1350 1303 1299 =STDEV([St1], [St2], [St3], [St4], [St5], [St6], [St7], [St8], [St9], [St10]) Standard deviation of breaking strength (27.46391572)