When creating formulas in Excel 2007 , we might sometimes use a constant values like pi for example when you wanted to calculate the area of a circle etc …

We could create constants in this case by assigning proper names and then use the names instead of the values in the formulas .
To Create a constant , follow the steps below

1. Click on the Define Name Button in the formulas tab .

2. Enter the name for the constant in the New Name Dialog Box .You can also  define the range for the name defined to be the worksheet or for the entire workbook .
Eg : constant1

3. In the Refers To Textbox , add the value for the constant prefixed with the equal symbol and click ok
Eg : = 15

Now enter the name of the constant in the formula prefixed with equal symbol and you will see the value 15 in the cell .