Help with creating Matrix table Delta

Hi Pijush,

I have attatched a sample of the data at the bottom below, unfortunately i could not use the exact data as it is for work but i recreated the file with only relevent information to my request. In the sample data is three columns, the SLOC column is an identifier which makes up the rows of my matrix in PowerBI, the total cost column makes up the values in my PowerBI matrix and finally the calender week column would make up the columns in my matrix. 

The screenshot attatched below shows my requirment, is there a way to create an additional column here in this matrix that would show the Delta between the displayed Weeks?