"New calculated Item" in Pivot Table

I came across this intresting option sometime back.

I have five sales stage 1 to 5. But I needed to display in the same row / column the sum of stages 1 and 2. To achieve it I used the calculated item option which is provided in the
pivot table.

Steps:
1. Click on any row / column for which you need a new calculated item.

2. In the window that appears, give a name as it must appear in the UI. Create the forumla.I have given sum of two sales stages.

3. The result will be as shown below. We have a new value which has sum of the two sales stages.


But, we need to remember that the calculated items appear in the same order as they were created.