Zend certified PHP/Magento developer

How do I represent the change of a value in a single cell in another cell?

I am trying to track the change in value in a set of cells on a week to week basis. I have a large data set and a “dashboard” that auto-populates when I paste new data every week. I have a set of cells that contains the sums of this data, and each week those sums change due to the data changing. I want to have another set of cells that show the amount of increase or decrease that occurred in the set of cells that represent the sums. How can I do this?

This shows the “sums” cells and the cells where the change will be displayed:
Here shows the "sums" cells and the cells where the change will be displayed.