Slow measure performance for P&L table

DAX DAX Calculations
6

Thanks Antriksh. Yes I am using that item but it seems to be having no impact on timings if I switch it off. I need that to maintain the structure.
No there is no Distinct in the code. Below is the DAX I used.

Actuals = 
VAR CurrentItem = SELECTEDVALUE('IS Template'[Items (Normalized)])

Return

SWITCH(TRUE(),

    CurrentItem = "Total Revenues", [Total Revenues],
    CurrentItem = "Total Operating Expenses", [Total Operating Expenses],
    CurrentItem = "EBITDA", [EBITDA],
   
    CALCULATE([TB Values],'P&L Mappings'[TB Items Mapping]=CurrentItem))