Help with sumif from multiple tables

I am trying to calculate the blue highlighted columns in PowerBI in order to get the two graphs. I have the table in sheet 2 available. I am building the relationship to be between PO Date and Date. I get an error saying my expression containts columns from multiple tables. My formula is calculate(sum('Table1' [% Total Cost]),'Table 1'[PO Date]<'Table2'[Date]

Thank you!