When you format a cell to display percentages, Excel assumes that whatever you enter into that cell in the future will be a percentage. Thus, if you enter the number.5, Excel translates the value as 50%. Likewise, if you enter .75, then Excel treats the value as 75%.
A potential problem comes into play, however, when you start to enter numbers greater than or equal to one. For instance, if you put in the number 12, do you mean 12% or 1200%? By default, Excel thinks you mean the latter. Excel includes a control that allows you to specify how you want it to interpret what you enter. If you want Excel to treat the value as 12% instead of 1200%, then you can follow these steps:
- Display the Excel Options dialog box. (In Excel 2007 click the Office button and then click on Excel Options. In Excel 2010 display the File tab of the ribbon and then click on Options.)
- At the left side of the dialog box, click Advanced. (See Figure 1.)
- Make sure the Enable Automatic Percent Entry check box is selected.
- Click on OK.
Figure 1. The advanced options tab of the Excel Options dialog box.
Remember-this configuration change only comes into play for cells that are already formatted to contain percentages. It has no effect on any cells formatted in any other way.