How to Find the Probability Near the Mean with GAUSS in Excel

Use GAUSS to find the share of values between the average and a point — and within any band around it.

You will learn to

• Find the share between the mean and a z-score
• Find the share within ± k standard deviations
• Find the share between two real values

How it works

GAUSS(z) returns the probability that a standard normal value falls between the mean and z standard deviations from it. It equals NORM.S.DIST(z,TRUE) − 0.5, so =GAUSS(1) returns about 0.341 and =2*GAUSS(1) gives the famous 68% within one standard deviation.

For negative z, GAUSS is negative, which makes ranges easy: the share between two values is GAUSS(z of the upper value) − GAUSS(z of the lower value), whichever side of the mean they sit on.

=2*GAUSS(1)