SUM and the =OFFSET function (Sample)

Sometimes it is necessary to base a calculation on a set of cells in different locations.

An example would be when a total is required from certain months of the year, such as the last 3 months in relation to the current date.

One solution would be to retype the calculation each time new data is entered, but this would be time consuming and open to human error.

A better way is to indicate the start and end point of the range to be calculated by using the =OFFSET() function.

The =OFFSET() picks out a cell a certain number of cells away from another cell. By giving the =OFFSET() the address of the first cell in the range which needs to be totalled, we can then indicate how far away the end cell should be and the =OFFSET()will give us the address of cell which will be the end of the range to be totalled.

The =OFFSET() needs to know three things;

1. A cell address to use as the fixed point from where it should base the offset.

2. How many rows it should look up or down from the starting point.

3. How many columns it should look left or right from the starting point.

Using =OFFSET() Twice In A Formula

The following examples use =OFFSET() to pick both the start and end of the range which needs to be totalled.

Example

The following table shows five months of data.

To calculate the total of a specific group of months the =OFFSET() function has been used.

 The Start and End dates entered in cells F71 and F72 are used as the offset to produce a range which can be totalled.

Explanation

The following formula represent a breakdown of what the =OFFSET function does.

The  formula displayed below are only dummies, but they will update as you enter dates into cells F71 and F72.