Reference Multiple Columns

Above is an example table of data where I'm looking to create the 'DelValue' column with DAX.
The 'DelValue' column is  'Value'- 'RefValue' derived from:
(Run = 2, ATD=1, Value=4) - (Ref=1 becomes Run=1, ADT=1, Value=6)
In this example the Ref assumes the Run, the ATD matches and the two values, Value and RefValue a subracted to create the DelValue.
My current path has been to find the RefValue with the Run and Ref switch and matching ATD then subtract the value of the Run, but i'm having very little succes and could use a few more options.

I can complete this with joining tables and matching Ref , ATD to Run ATD, but would really like to do this with the table join process as it is heavy on compute.

Any help is appreciated 🙂