Need help in optimizing DAX query

Greg_Deckler AlexisOlson 
I think i did made it more effeciant with what you guys have suggested.

Now the query is running in less than a sec.

here is it

VAR _Table = CALCULATETABLE( 'Inventory Snapshots', KEEPFILTERS('Inventory Snapshots'[Snapshot Weekly?] = "Y"), KEEPFILTERS('Calendar'[445 Year Week Offset]=0))
VAR _Onhand_StdCost = SUMX( _Table, [On-hand StdCost$])
VAR _PickedQty = SUMX( _Table, [Picked Qty])
VAR _currency = MAX( 'Inventory Snapshots'[Currency]) --USD
 
VAR _currencySelected = 
MAXX(ALLSELECTED('Exchange Rates'[To Currency]), 'Exchange Rates'[To Currency])

VAR _ConversationRate = 
        LOOKUPVALUE (
            'Exchange Rates'[Exchange Rate],
            'Exchange Rates'[To Currency], _currencySelected
            ,'Exchange Rates'[From Currency],"USD"
        )*1
RETURN

IF(_currencySelected = "USD",(_Onhand_StdCost+_PickedQty),
(_Onhand_StdCost+_PickedQty*_ConversationRate))

As i said the culprit was switch...but before that i see it was having major concern at selectedvalue of to currency.

So i did change it to 

VAR _currencySelected = 
MAXX(ALLSELECTED('Exchange Rates'[To Currency]), 'Exchange Rates'[To Currency])

And We have USD value also in To Currency which should get multiplied by 1, So i tried to avoid that condition by making it into a final switch case with less condition.

VAR _ConversationRate = 
        LOOKUPVALUE (
            'Exchange Rates'[Exchange Rate],
            'Exchange Rates'[To Currency], _currencySelected
            ,'Exchange Rates'[From Currency],"USD"
        )*1
RETURN

IF(_currencySelected = "USD",(_Onhand_StdCost+_PickedQty),
(_Onhand_StdCost+_PickedQty*_ConversationRate))

Greg_Deckler  You are my guardian angel whenever i get struck with these sort of situations. You always comes to rescue me. Keep doing what you are doing. ❤️

Thanks.

Mohan V.