S&OP, Demand Planning & Forecasting worked example

Bias Correction Savings at 69% share of bias eliminated by retuning: a worked example

Push share of bias eliminated by retuning up to 69% and the picture changes. This example computes every intermediate figure at that operating point. A forecast analyst uses it to justify the effort of re-fitting models that consistently run high or low.

The inputs for this scenario

  • Annual units under biased forecast: 9,000 units (unchanged)
  • Cost of forecast bias per unit: 6.5 $/unit (unchanged)
  • Share of bias eliminated by retuning: 69 % (raised for this scenario; the documented default is 60)
  • One-time model retuning cost: 1,800 $ (unchanged)

Working through the calculation

  • Applying the documented formula (Total savings = biased units x cost of bias per unit x bias removed % + retuning cost) to the inputs above produces each figure below.
  • At this operating point the engine returns 42,165 $ for total bias correction savings cost, the number this scenario is built around.
  • At this operating point the engine returns 4.68 $ / piece for bias correction savings cost per unit.
  • At this operating point the engine returns 40,365 $ for variable bias correction savings cost.
  • At this operating point the engine returns 1,800 $ for fixed bias correction savings adder.

How this compares with the baseline

  • Against the tool's baseline example, where share of bias eliminated by retuning sits at 60% and the headline result is 36,900 $, this scenario comes in 14.27% above the baseline at 42,165 $.
  • It computes total savings from removing a share of forecast bias across your biased volume, plus the fixed retuning cost, and expresses it per unit. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Total bias correction savings cost: 42,165 $ (headline result)
  • Bias correction savings cost per unit: 4.68 $ / piece
  • Variable bias correction savings cost: 40,365 $
  • Fixed bias correction savings adder: 1,800 $

Run it with your numbers

  • Every input above is editable in the live Bias Correction Savings calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.