Please help to calculate dynamic per row difference

Dear colleagues,

Please help me to understand, how can I calculate the NPS impact before and after including different categories of my table. This must be done for each "Section" so I can add it as a column. I know how to do it manually, but I can't come up with a function 😞

For example, I have a simple NPS table with records like this:

I want to calculate the NPS and combine it with each Section to see the overall results. Even though I see that "Quality" is the main pain point, and I would like to understand what positive or negative impact each "Section" has on the overall NPS and I can add it as a column after.

I know how to calculate the impact for the Quality - I can manually exclude it from the view and see the difference. Then, I can divide the difference and calculate the percent of that influence but I would like to have it dynamically calculated so I can build different charts and breakdowns after. I don't know if I need a column or a measure to make it work.

I would really appreciate any ideas. 
Thank you very much and God Bless your hard work!