STDEVPA

The STDEVPA function returns the standard deviation—a measure of dispersion—of a set of any values, based on the population (true) variance.

STDEVPA(value, value…)

value: Any value. value can contain a single value or collection. All values must be of the same value type (except that string values and boolean values can be included with number values). A minimum of two values are required. A string value can be included in a referenced cell, but can’t be directly entered as an argument to the function.

value…: Optionally include one or more additional values or collections of values.

Notes

It is appropriate to use STDEVPA when the specified values represent the entire collection or population. If the values you are analyzing represent only a sample of a larger population, use the STDEVA function.
The function assigns a value of 0 to any string value, 0 to the boolean value FALSE, and 1 to the boolean value TRUE and includes them in the computation, if all other values are numbers. If there are date/time values or duration values included with string values or boolean values, the function returns an error. Empty cells are ignored.
The standard deviation is the square root of the variance returned by the VARPA function.

Example
Suppose you installed a temperature sensor in Cupertino, California. The sensor records each day’s high and low temperatures in degrees Fahrenheit. The data from the first few days of July is shown in the following table and is used as a sample for the population of high and low temperatures (note that this is an example only; this would not be statistically valid). On July 5, the sensor failed, so the data in the table shows n/a, or not available.

Example

Suppose you installed a temperature sensor in Cupertino, California. The sensor records each day’s high and low temperatures in degrees Fahrenheit. The data from the first few days of July is shown in the following table and is used as a sample for the population of high and low temperatures (note that this is an example only; this would not be statistically valid). On July 5, the sensor failed, so the data in the table shows n/a, or not available.

	A	B	C
1	Date	High	Low
2	07/01/10	58	58
3	07/02/10	84	61
4	07/03/10	82	59
5	07/04/10	78	55
6	07/05/10	n/a	n/a
7	07/06/10	81	57
8	07/07/10	93	67

Date

High

Low

07/01/10

07/02/10

07/03/10

07/04/10

07/05/10

n/a

07/06/10

07/07/10

=STDEVPA(B2:B8) returns approximately 29.4472894702188, the dispersion (standard deviation is a measure of dispersion) as measured by STDEVPA, of the sample of daily high temperatures.

If you had a large data set that could not easily be visually scanned, or you wished to automate checking for missing values, you could compare the results of=STDEVP(B2:B8), which returns approximately 10.6092203085597, and STDEVPA, which returns approximately 29.4472894702188. If (as in this case) they are not equal, it would indicate the data set contains text (such as “n/a”), or one or more boolean values (TRUE or FALSE).