Press the Enter key on the keyboard to complete the formula. B2 1-C2 First Excel will calculate the formula 1-C2. On the Home tab click the Percentage button.
Next divide this result by the old number in cell A1.
To calculate the difference as a percentage we subtract this months value from last months and then divide the result by last months value. The answer 67 should appear in cell E6. Cell C2 contains the number 20 equal to the 02 value. To show percentages apply the Percentage number format to the formula cells.