PO can be partial deleted or fully deleted. Partial deleted when PO still have some active line item that valid for good receipt or Invoice. Fully deleted when all the line items are deleted. You need to create custom report to get this information from the system.
You figure out the Purchase orders from EKPO table where EKPO-LOEKZ indicator is equal to L. Then to get date, You need to figure out all change documents using table CDHDR and CDPOS in combination to figure when was the last update for field LOEKZ was happened for the PO. Then you get date when the Deletion indicator was set.
Recommendation- Do not put deletion date in selection screen for the report. As CDHDR and CDPOS are huge table and you will have performance issues for the report.
Thanks,
Jagdeep