When a forecast quantity and a firm order for the same period both count as demand, forecast consumption is not netting them together. Forecast consumption is the rule that prevents double counting: a firm order is meant to consume part of the forecast for its period so the two do not stack. EDGEBIC by User Solutions reconciles forecast and orders through a consumption rule, and configuring that rule is what stops the doubled demand.
This post is part of the EDGEBIC troubleshooting guide. It explains what forecast consumption does, the two consumption rules, and why a period mismatch defeats them.
Why Demand Looks Doubled
A forecast is an estimate of demand for a period. A firm order is real demand that arrives against that estimate. If both count in full, the plan orders material and capacity for the sum, and it builds far more than the market needs. Forecast consumption exists to prevent exactly this: as real orders arrive, they consume the forecast for their period rather than adding to it.
So doubled demand has a specific meaning. It says the order and the forecast are being treated as two separate quantities instead of one demand that the order is drawing down. Either the consumption rule is not applied, or the order and the forecast are not landing in the same period for consumption to match them.
The Two Consumption Rules
Consumption reconciles a period's forecast with the orders against it, and there are two documented ways to do that. How forecast consumption works covers both in depth, and the greater-of versus minus-consumed comparison shows when each fits.
| Rule | How it sets a period's demand | Fits when |
|---|---|---|
| Greater-of | The larger of the forecast and the actual orders | Orders roughly track or exceed the forecast |
| Minus-consumed | The forecast reduced by the orders already consumed, plus the orders | You want remaining forecast to carry alongside orders |
Under the greater-of rule, a 500 forecast with 300 of orders nets to 500, not 800: the orders consume part of the forecast rather than stacking on it. If orders reach 600, demand becomes 600, because real demand has passed the estimate and the plan should follow it. Either way, the forecast never adds on top of the orders, which is what stops the double counting.
When a Period Mismatch Defeats Consumption
Consumption reconciles demand within a period. If the forecast sits in one bucket and the firm order lands in the next, consumption cannot match them, and both count as separate demand. This is where time fences and bucket alignment matter: a fence or a bucket boundary that separates the order from the forecast it was meant to consume produces exactly the doubled demand you are seeing, even with a consumption rule in place.
So the diagnosis has two branches:
- Is a consumption rule configured at all? If not, forecast and orders always stack. Choose the rule that matches how your orders arrive against forecast.
- Do the order and the forecast share a period? If the order fell in a different bucket, align the order to the forecast period or the fence to the bucket boundaries so consumption can net them.
The Fix
- Confirm which consumption rule is set for the product, greater-of or minus-consumed.
- Confirm the firm order and the forecast fall in the same period.
- If the rule was missing, apply the one that matches your order pattern.
- If the period was mismatched, align the order or the fence so the two meet.
- Recompute demand and confirm the period nets to the larger figure rather than the sum.
For the broader set of forecast and replenishment pitfalls, see the sibling forecasting and replenishment mistakes. The troubleshooting guide links the neighboring planning symptoms.
Because forecast consumption is not netting the firm order against the forecast in that period. Forecast consumption is the rule that prevents double counting: a firm order for a period is meant to consume part of the forecast for that period, so the two do not stack. When the consumption rule is not applied, or the order and forecast fall in different buckets, both count in full and demand looks doubled.
Forecast consumption is the logic that reconciles a forecast with the actual orders that arrive against it. As real orders come in, they consume the forecast for their period rather than adding to it, so total demand reflects the greater of the two rather than their sum. Without consumption, a plan would order material and capacity for both the forecast and the orders, building far more than the market actually needs.
The greater-of rule sets a period's net demand to the larger of the forecast and the actual orders, so whichever is bigger drives the plan. The minus-consumed rule reduces the forecast by the orders already consumed, leaving the remaining forecast plus the orders. They handle over-consumption and under-consumption differently, so choosing the one that matches how your orders arrive against forecast is what stops the double counting.
Yes. If the forecast and the firm order fall in different periods because of how buckets or time fences are aligned, consumption cannot match them, and both count. Consumption reconciles demand within a period, so a forecast in one bucket and an order in the next are treated as separate demand. Aligning the order to the forecast period, or the fence to the bucket boundaries, lets consumption net them.
Expert Q&A: Deep Dive
Q: We forecast 500 units for July and took a firm order for 300 in July, but the plan is building 800. Why is it not building 500?
A: The plan is building 800 because the 300-unit order is not consuming the July forecast: both are counting in full. With forecast consumption applied under the greater-of rule, July's net demand would be the larger of the 500 forecast and the 300 of orders, which is 500, so the plan builds 500 rather than 800. Check that the consumption rule is configured and that the order and the forecast fall in the same period. If the order landed in a different bucket than the forecast, consumption cannot match them and both count.
Q: Orders came in above forecast for one product. How should consumption handle that, and will it still stop double counting?
A: When orders exceed the forecast for a period, the greater-of rule sets demand to the orders, since they are now the larger number, so the forecast is fully consumed and does not add on top. That is the correct behavior: real demand has surpassed the estimate, and the plan should follow the orders. Consumption still prevents double counting because the forecast never stacks on the orders; it is either partly consumed or fully consumed, never added. Confirm which rule is set so you know whether the remaining forecast, if any, carries forward.
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