Do this as a check. I want you to find the values asked for by hand as practice for the test.
Statdisk does not find the variation for you. Another name for Variation is Sum of Squares, but the Sum of Squares under the Statistics box is the uncorrected sum of squares, which is what you get if you just square the values and add them up, not the value we want which is found by subtracting the mean before squaring the values.
You should get some output window similar to what is shown to the right.
Check the sample size, mean, median, variance, and standard deviation with what you calculated by hand.