Reporting Functionality | Power BI paginated Reports| SSRS

Hello,

I need to create a report on Power BI paginated report which is similar to SSRS  ,where I need to show a report as given below.

From the report which I have created got the result as below. 

Now I need to generate a new column called TestNo column which need to be included in my result shown above. But it should be based on SDIDATAITEMID value which I have shown above. It should give me the values as 

TestNo

8043366 - 1

8043367 - 2

8043368 - 3

8043369 - 1

8043370 - 1

8043371 - 2 ,.... Likewise....

I can provide more info if someone could help me here.