Calculate Columns in a Matrix Visual

Can anyone help me with this please. I have a summary visual based on table below and when any visual fields are clicked on ie yellow £150 then the visual below shows the 2 x transactions from the table making up this value.

My issue is that as the transaction table rows contain the type which is used for the visual. I want to be able to apply calcuated column to my visual as highlighted in green. Does anyone have any ideas to make this work?

Thanks