Читать книгу Excel Data Analysis For Dummies - Paul McFedries - Страница 35

If you want to study the effect that different input values have on a formula, one solution is to set up the worksheet model and then manually change the formula’s input cells. For example, if you’re calculating a loan payment, you can enter different interest rate values to see what effect changing the value has on the payment.

The problem with modifying the values of a formula input is that you see only a single result at one time. A better solution is to set up a data table, which is a range that consists of the formula you’re using and multiple input values for that formula. Excel automatically creates a solution to the formula for each different input value.

Data tables are an example of what-if analysis, which is perhaps the most basic method for analyzing worksheet data. With what-if analysis, you first calculate a formula D, based on the input from variables A, B, and C. You then say, “What happens to the result if I change the value of variable A?” “What happens if I change B or C?” and so on.

Don’t confuse data tables with the Excel tables that I talk about in Chapter 3. Remember that a data table is a special range that Excel uses to calculate multiple solutions to a formula.