By Conrad Carlberg

The active cell on an Excel worksheet has a small square on its lower-right corner. That square is called the fill handle. You can use that fill handle to copy and paste the cell’s data in any direction. Just put your mouse pointer over the fill handle, press the mouse button, and drag down, right, left, or up.

This technique works both with formulas and constants. If you start with a multiple selection, you can extend a series of values such as 1, 2 to go as far as you’d like.

Suppose you have a set of revenue figures in cells A1:A500. You’d like to enter a 15 percent commission on each of those figures in B1:B500. You could enter this formula in cell B1:

=A1 * 0.15

Then click the fill handle in B1 and drag down through B500. The problem is that it’s tedious. You can even have the process, which Excel calls autofill, run away with you, and you’ll find yourself filling into B422865 before you know it.

The solution is to double-click the fill handle. Excel autofills whatever is in the active cell as far down as an adjacent list extends. In the example just cited, double-clicking B1’s fill handle autofills the formula down through B500.