Microsoft Excel has ten major statistical formulas, such as sample size, mean, median, standard deviation, maximum and minimum. The sample size is the number of observations in a data set, for example if a polling company polls 500 people, then the sample size of the data is 500. After entering the data set in Excel, the =COUNT formula will calculate the sample size. Sample size is useful for calculations such as standard error and confidence levels. Using Microsoft Excel will allow a user to quickly calculate statistical formulas since statistical formulas tend to be longer and complex than other mathematical formulas.

Enter the observation data in Excel, one observation in each cell. For example, enter data in cells A1 through A24. This will provide a vertical column of data in column A.

Type "=COUNT(" in cell B1.

Highlight the cell range of the data or type the cell range of the data after the "(" entered in Step 2 in cell B1, then end the formula with a ")". The cell range is any cells that have data in the cell. In this example, the cell range is A1 through A24. The formula in the example then is "=COUNT(A1:A24)"

Press "Enter" and the sample size will appear in the cell with the formula. In our example, cell B1 will display 24, since the sample size will be 24.