The system calculates the moving average price automatically by dividing the material value in the stock account by the total of all storage location stocks in the plant concerned. It changes the price with each valuation-relevant movement. 

The field “Moving Price” or the field "Per. unit price" can only updated manually in 2 cases:  

• for the creation of the view Accounting 1 of a Raw Material, Packaging or Trading goods (Z100, Z110, Z130). The price is provided by PtP.
• when there is a mistake in the calculation of the Moving price (it can come from an incorrect price in a purchase order). In this case the modification must be justified and will be controlled by the IAC 01.02

The field is never updated manually when the material code is produced & in material ledger plants