
When writing an Excel formula, there are two ways you can reference a cell: absolutely and relatively. 
For example, in cell B1 you may write =A1. The value in cell A1 will then be shown in cell B1. This is a relative reference. If you copy the contents of B1 to B2, the formula will now read =A2. The reference is based on the relative position of the cell that contains the formula and the cell to which the reference refers.
In our case, one cell to the left. 
An absolute cell reference always refers to a cell in a specific location. If you copy the formula to a new cell, the absolute reference remains the same. An absolute reference is written =$A$1. 
You can mix references, for example $A1. In this case the column is absolute and fixed, but the row is relative.


1. 
Select the cell containing the formula. 

Group Selection

2. 
In the formula bar (labelled fx at the top of the
spreadsheet), highlight the references to be changed. 
3. 
Press the F4 key. It will change the reference type. Keep
pressing and it will switch from one option to another. 


You have to highlight the formula otherwise pressing F4 will just repeat whatever action you last took, just like Ctrl Y does. 
