Does IPV only generated based on "Goods" type of PO, rather than "Fixed Price" Service PO.

Summary:

Does IPV only generated based on "Goods" type of PO, rather than "Fixed Price" Service PO? 

Content (required):

We found that when a difference amount between the "Goods” type of PO and Payable Invoice, an Invoice Price Variance account generate in invoice accounting entry. But IPV not generated for the invoice that match to fixed price service PO. So can tell is this the standard function.

If so, how to process the difference amount between fixed price po and payable invoice that matched to the type of PO

Version (include the version you are using, if applicable):

11.13.23.04.0

Code Snippet (add any code snippets that support your topic, if applicable):