ERP & MRP Planning worked example

Forecast Accuracy at 99% target forecast accuracy: a worked example in erp & mrp planning

What does the result look like when target forecast accuracy reaches 99%? The full calculation is worked below with real intermediate numbers. a demand planner needs to quantify forecast quality for a product family

The inputs for this scenario

  • Demand within forecast tolerance: 9,200 units (unchanged)
  • Total actual demand: 10,000 units (unchanged)
  • Target forecast accuracy: 99 % (raised for this scenario; the documented default is 90)

Working through the calculation

  • Applying the documented formula (Forecast accuracy = demand within forecast tolerance ÷ total actual demand × 100) to the inputs above produces each figure below.
  • At this operating point the engine returns 92 % for forecast accuracy, the number this scenario is built around.
  • At this operating point the engine returns 7 points for forecast accuracy gap to target.
  • At this operating point the engine returns 9,200 units for demand within forecast tolerance.
  • At this operating point the engine returns 10,000 units for total actual demand.

How this compares with the baseline

  • Against the tool's baseline example, where target forecast accuracy sits at 90% and the headline result is 92 %, this scenario lands almost exactly on the baseline at 92 %.
  • A figure at this level is achievable when target forecast accuracy is genuinely sustained, not just peaked for a shift. A single accuracy percentage hides direction and pattern — it does not tell you whether you over- or under-forecast, and it can look healthy while masking large errors on a few high-value SKUs.

Results at a glance

  • Forecast accuracy: 92 % (headline result)
  • Forecast accuracy gap to target: 7 points
  • Demand within forecast tolerance: 9,200 units
  • Total actual demand: 10,000 units

Run it with your numbers

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

Last reviewed 2026-05-12.