Microsoft Excel's CORREL function finds the mathematical correlation between two sets of data. A high coefficient, close to "1", suggests a strong correlation. A coefficient close to "0" suggests little or no correlation. A coefficient close to "1" suggests a correlation that's strong but negative because an increase in one variable leads to a decrease in the other. Using the CORREL function saves you from having to type out a long and complex statistical formula relating the two data sets.

Paste the following formula "=CORREL(A2:A6,B2:B6)" into a blank cell in your spreadsheet.

Replace "A2" with the address of the cell that contains your first data set's first item.

Replace "A6" with the address of the cell that contains your first data set's last item.

Replace "B2" with the address of the cell that contains your second data set's first item.

Replace "B6" with the address of the cell that contains your second data set's last item.

Press the "Enter" key. The cell's value will change to the correlation coefficient that relates the two arrays of data.