Summarizing Data That Meets Specific Conditions

To create a conditional formula, you click the cell to hold the formula and open the Insert function dialog box. In the dialog box, select IF from the list of available funtions and then click OK. The Function Arguments dialog appears. The Logical_test box you want to check. Then you enclose the message in quotes in the Value_if_true or if_false box. Then in the IFERROR function enables you to display a custom error message instead of relying on the default Excel 2007 error messages to explain what happened. If function finds a match for the CustomerID, if it doesn't find a match, it displays the text Customer not found. This is what you do.