Calculate Demand Forecast (whina2202m000)

Use this session to calculate the demand forecast by item for a range of future periods.

LN uses the demand forecast when calculating the safety stock for each period:

S (n) = K * 1.25 * MAD (n) Sqrt ((Oint * 5/7 + Oltm + Sftm) / Period Length)
S safety stock
K safety factor determined by LN on basis of service level
MAD mean absolute deviation
Oint order interval
Oltm order lead time
Sftm safety time
Period Length (52 * 5)/number of periods

And when calculating the reorder point:

ROP reorder point
Dem.forec. demand forecast
Oltm order lead time
Oint order interval
Sftm safety time
S safety stock
Period Length (52 * 5)/number of periods

The number of periods for calculating the safety stock and the reorder point must be determined based upon period type and the number of periods as defined in the Items - Ordering (tcibd2100m000) session and the Item Data by Warehouse (whwmd2110s000) session.

Updates

The Safety Stock field and the Reorder Point field in the Items - Ordering (tcibd2100m000) session will be updated for the specified items with the values calculated for the period in the farthest future, if the Lot Size Calculation Allowed check box in that session and the Item Data check box are selected.

If the Item Data by Warehouse check box is selected, the following fields in the Item Data by Warehouse (whwmd2110s000) session are updated:

  • Expected Annual Issue
  • Safety Stock
  • Reorder Point

For all items specified, the Expected Annual Issue field in the Item - Warehousing (whwmd4600m000) session will be updated.

The demand forecast by period is updated for the specified items in the following sessions:

  • Item Issue by Period (whinr1120s000)
  • Item Issue by Warehouse and Period (whinr1130s000)
Note: 
  • The Year/Period and To fields of the Year/Period field must fall in the year entered in the corresponding year in the Year/Period of Usage From field.
  • To preview the calculation results in a report before the demand forecasts are actually updated, select Simulate.
  • If the Item Issue by Period field and Item Issue by Warehouse and Period field of the Inventory Reporting Parameters (whinr0100s000) session are cleared, the Calculate Demand Forecast (whina2202m000) session is aborted.

Field Information

Selection Range
Year/Period of Usage From

The year from which LN starts analyzing the demand forecast.

Year/Period of Usage From

The period of the year, that is specified in the Year/Period of Usage From field, from which LN starts analyzing the demand forecast.

Update
Simulate/Update

To preview the calculation results in a printed report before the demand forecasts are actually updated, select Simulate.

Default value

Simulate

Item Data

If this check box is selected, LN updates the general order data in the Items - Ordering (tcibd2100m000) session.

Item Data by Warehouse

If this check box is selected, the value is written to the relevant field in the Item Data by Warehouse (whwmd2110s000) session provided that the Update Inventory/Order Data field in the Item Data by Warehouse (whwmd2110s000) session is selected and the item warehouse status is Active.

Item Data by Site

If this check box is selected, the value is written to the relevant field in the Warehousing Settings by Site (whwmd2101m000) session provided that the Update Inventory/Order Data field in the Item Data by Warehouse (whwmd2110s000) session is selected and the item warehouse status is Active.

For Calculation Use
For Calculation Use

The method used by LN for the demand forecast calculation.

Allowed values

Qualified Demand Quantity

LN calculates the demand forecast based on the qualified demand quantity of the item.

Actual Issues

LN calculates the demand forecast based on the Actual Issues of the item.

Demand Direct Delivery Quantity

The Demand Direct Delivery Quantity can be taken into account for the demand forecast. The value will be added up to either Actual Issue by Period or Qualified.

Returned Quantity

The Returned Quantity can be taken into account for the demand forecast. If this check box is selected, LN automatically subtracts the Returned Quantity from the Qualified Demand Quantity field of the Item Issue by Period (whinr1520m000) session and the Item Issue by Warehouse and Period (whinr1530m000) session.

Note: 

The Returned Quantity check box is disabled if the forecast calculation is based on Actual Issue by Period.

The Returned Quantity check box is enabled if the forecast calculation is based on qualified demand quantity.

Lost Sales

The Lost Sales can be taken into account for the demand forecast. The value will be subtracted from qualified demand quantity.

Lost Sales is only relevant if the demand forecast calculation is based on Qualified Demand, and the Qualified Demand is populated by the Actual Demand. The Actual Demand represents the total customer demand in a certain period, irrespective if the demand is shipped to the customer or cancelled. For a more realistic picture, the canceled orders, which are Lost Sales, can optionally be subtracted from the Actual Demand.

Note: 

The Lost Sales check box is cleared and disabled if the forecast calculation is based on Actual Issue by Period.

The Lost Sales check box is enabled in case the forecast calculation is based on qualified demand quantity.

Number of Future Periods

The number of future periods for which LN calculates the demand forecast by item. For more information, refer to To calculate demand forecast for each period

Print Forecast Calculation

If this check box is selected, a forecast calculation is printed.

Year/Period

The year from which LN starts generating the report of the forecast demand.

Year/Period

The period of the year, that is specified in the Year/Period field, from which LN starts generating the report of the forecast demand.

Year/Period

The last year for which LN generates the report of the forecast demand.

Year/Period

The last period of the year, that is specified in the Year/Period field, for which LN generates the report of the forecast demand.

Detailed Report

If this check box is selected, LN prints the detailed demand forecast data.

If this check box is cleared, LN prints the summarized demand forecast data,

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