Forecast Accuracy & MAPE Scorecard
Track forecast accuracy, MAPE, Bias, and WMAPE. Enter values for instant results with step-by-step formulas.
Frequently Asked Questions
What is the difference between MAPE and WMAPE?
MAPE averages the percentage errors directly. WMAPE sums the absolute errors and divides by total actuals, effectively weighting the error by the volume of the item.
Why is my MAPE infinite?
If any 'Actual' value is 0, division by zero occurs. Use WMAPE or MAE (Mean Absolute Error) for data sets with zeros.
How can I improve forecast accuracy?
Clean historical data (remove outliers), use appropriate statistical models (seasonality), and incorporate market intelligence (promotions, competitor actions).
Should I forecast revenue or units?
Operations needs units (to build/buy). Finance needs revenue. Forecast in units first, then apply pricing to get revenue.
What is Forecast Value Added (FVA)?
FVA measures if a process step (like manual review) improved the forecast compared to a naive baseline (like 'same as last month').
Why do I have high accuracy but stockouts?
You might have high volatility within the period (e.g., all sales happened on day 1, but stock arrived day 15) that monthly aggregates hide.