Microsoft Excel can be used as a calculator. The following example shows subtraction. You can use other symbols to add, multiply, divide, and perform other calculations.

1. Double-click on a cell to begin editing it. In this case, we double-click on cell L2. We type a formula for subtraction and use cell references: =J2-K2
2. Press "Enter" or "Return" on the keyboard to commit the changes to cell L2. Then click on cell L2 again. This will place a small square at the bottom right of the cell.
3. We can drag this formula across multiple cells. Move the cursor over the small square so it turns into a very small + symbol.
4. Click, hold, an drag that square to apply the formula to cells L3 to L7.