iWork '09: The Missing Manual

Conditional Formats for “Content Alerts”

Cell formatting isn’t only about aesthetics; they can also be part of your own homegrown data surveillance system. Numbers lets you add tripwires to cells to trigger a change in formatting when the cell’s value meets a certain set of conditions. You might make the cell with your bank balance turn bright red, for example, when your funds get dangerously low (an event that might meanwhile make you turn a sickly green). You can similarly highlight to-do items whose due dates are closing in, or revenue figures for sales reps who’ve met their monthly quota.

Note

You can’t set conditional formatting for summary cells in a category row.

To apply conditional formatting, you select one or more cells and then define rules to trigger new formatting. Each rule specifies its own visual effect to associate with cells when they meet the rule’s conditions. You might make your checking account balance turn amber when it dips under $250 and then bright red and bold letters when it goes under $50, for example. When the cell doesn’t meet any of the conditions you add, nothing happens, and the cell simply displays as it normally would. Here’s how to set it up:

1. Select one or more cells.

2. Choose Format → Show Conditional Format Rules, or click the “Show rules” button under Conditional Format in the Cells Inspector.

   Numbers opens the Conditional Format window, shown in Figure 19-19.

3. Choose an option from the “Choose a rule” pop-up menu.

   The options in the top section of ...