Formulas and Functions

Table Of Contents

STDEV

The STDEV function returns the standard deviation, a measure of dispersion, of a

collection of values based on their sample (unbiased) variance.

STDEV(num-date-dur, num-date-dur…)

Â num-date-dur: A value. num-date-dur is a number value, a date/time value, or a

duration value.

Â num-date-dur…:One or more additional values (a minimum of two values are

required). All num-date-dur values must be of the same type.

Usage Notes

It is appropriate to use STDEV when the specied values represent only a sample of Â

a larger population. If the values you are analyzing represent the entire collection or

population, use the STDEVP function.

If you want to include text or Boolean values in the computation, use the STDEVA Â

function.

The standard deviation is the square root of the variance returned by the VAR Â

function.

Example

Assume you have administered ve tests to a group of students. You have arbitrarily selected

ve students to represent the total population of students (note that this is an example only; this

would not likely be statistically valid). Using the sample data, you could use the STDEV function to

determine which test had the widest dispersion of test scores.

The results of the STDEV functions are approximately 22.8035, 24.5357, 9.5026, 8.0747, and 3.3466. So

test 2 had the highest dispersion, followed closely by test 1. The other three tests had low dispersion.

Test 1 Test 2 Test 3 Test 4 Test 5

Student 1 75 82 90 78 84

Student 2 100 90 95 88 90

Student 3 40 80 78 90 85

Student 4 80 35 95 98 92

Student 5 90 98 75 97 88

=STDEV(B2:B6) =STDEV(C2:C6) =STDEV(D2:D6) =STDEV(E2:E6) =STDEV(F2:F6)