Click the Indexes icon in the Group Level group on the Forecasting tab or select Indexes from the Navigator’s context menu to use a group level seasonal index for all items within the group. Please see Indexes in Working with Hierarchies for more details.
Indexes uses the following modifier:
- \INDEXES: Directs Forecast Pro to calculate the seasonal indexes at the indicated group level and use them to de-seasonalize the histories for the nested items and groups. The de-seasonalized series are then forecasted and as a final step re-seasonalized. This approach works well when the items share the same seasonality. It allows one to deal with items whose histories are too short to extract seasonality directly. You cannot use \INDEXES if the group level includes zeros or negative numbers. You cannot nest \INDEXES groups within each other. Model parameters are re-estimated for each item of the \INDEXES group.