Measure how spread out a set of values is around the average.
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=STDEV.S(A2:A100)STDEV.S computes the standard deviation of a sample; STDEV.P is for an entire population. A larger value means more variability. Pair it with AVERAGE to describe a dataset.
=STDEV.S(Scores)→12.4Spread of the sample scores.
=STDEV.S({2,4,4,4,5,5,7,9})→2.14Sample standard deviation of eight values.
=STDEV.P({2,4,4,4,5,5,7,9})→2The same values treated as a whole population.
Whole population
=STDEV.P(A2:A100)Use when the data is the full population.
Use STDEV.S when your data is a sample of a larger group; STDEV.P when it's the entire set.
They return the same result. STDEV is the older name kept for compatibility; STDEV.S is the current one.
Use =VAR.S(A2:A100) for a sample or =VAR.P(A2:A100) for a population. Variance is the standard deviation squared.
In Excel 365 filter first: =STDEV.S(FILTER(B2:B100, A2:A100="East")).
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