Combining several separate Excel formulas together into one more complex formula reduces clutter in your workbooks and make them much easier for others to read. Excel beginners often use one cell to hold a formula, another to hold a second, and then perhaps a third to refer to results of formulas one and two. Adding a number of extra columns to a workbook for the express purpose of holding extra "helper formulas" is a fast way to work, but workbooks can quickly get out of control.