Unable to Populate "Physical Percent Complete" in Manage Financial Project Plan

Summary:

I have a project with assigned tasks, and some actual costs have already been captured from the Accounts Payable (AP) module. However, I am unable to populate the "Physical Percent Complete" field at the level of the Manage Financial Project Plan.
Could you please advise what additional setup or steps are required to make this field editable or automatically populated?

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