Using selected columns of a Pivot in Table Calculations

I have a query result with a Pivot in it. The data looks as shown below: 

I have Type_A to Type_F as my pivoted columns, I want to add up the columns Type_C and Type_D using one table calculation and add up the rest of the columns of the pivot in another table calculation. Is this possible? I tried to do this using pivot_index, but new types keep getting added to the data so I can’t reliable use pivot_index. 

Is there a way I can use the name of the Pivot column in a table calculation?