Sales prices on 'base' demand history records created by Generate demand history are calculated as ΣAmount/ΣSalesQty over the sales order or sales invoice lines used to generate each record, converted to the item's forecasting unit if this is different from the unit on the sales line.
Sales prices on 'base' forecast records created by Generate base forecast are calculated as ΣAmount/ΣSalesQty, totalled over the demand history records used to generate each forecast record that have Start dates that lie within the most recent 'Number of sales price calculation periods' specified in the Forecasting parameters. For example, if monthly forecasts are generated from 1/1/2023 and the Number of sales price calculation periods is 12, demand history records dated 1/01/2022 to 31/12/2022 will be used.