Calculate the deviation from the mean by subtracting each value from the mean you found in Step 1. It varies from sample to sample in a way that cannot be predicted with certainty. The sample mean of the series X that was shown above is 9635.
The population mean is the average of all the items in a population.
Square the numbers you calculated in Step 2. Sum of all observations divided by the number of observations but there is a big difference between how they are represented. The sample mean of the series X that was shown above is 9635. Divide sum by the number of samples.