percent of total for a calculated measure column

[Anonymous]

I need the percent of total for current years and prior years columns. I made a measure for Current years that works:

Sales % Total = 'Order_Line_Invoice'[SalesSUM]/CALCULATE(sum('Order_Line_Invoice'[Sales]),ALLSELECTED())

Prior year is a calculated measure: 

SalesPY =
CALCULATE (
Order_Line_Invoice[SalesSum],
SAMEPERIODLASTYEAR(Dates_INV[Date]))

I cannot make the Percent of Total for that. It will not let me apparently use my SalesPY measure in a Calculated Measure. 

Recommendations?