Case Studies/Retail & Consumer Goods
Retail & Consumer Goods·National Retail Group, 340 Stores·

ML Demand Forecasting Eliminating $4M in Annual Stockouts

3.2×
Accuracy Improvement
$4M
Stockout Cost Eliminated
94%
Forecast Accuracy
340
Stores Covered

A national retail group with 340 stores was losing $4M a year to stockouts. Their spreadsheet-based demand planning couldn't factor in weather, trends, or competitor signals. We built ML forecasting models trained on five years of sales data plus external signals. Forecast accuracy went from 61% to 94%. Predictions now feed directly into ERP replenishment workflows.

Client Background

The retailer runs 340 stores across 8 regions with 15,000 SKUs across apparel, homewares, and electronics. A central team of 6 planners managed demand forecasting with Excel models. Those models worked well enough for stable products. But they consistently missed on seasonal items, new launches, and anything sensitive to external factors like weather.

The Challenge

Stockouts clustered in three categories. Seasonal products saw demand spikes that the models consistently underestimated. New launches had no historical data to lean on. Regionally variable products got drowned out by national averages. The planning team knew the models weren't good enough. They just didn't have the tools to fix them.

61% forecast accuracy on seasonal products — below the industry benchmark of 75%

$4M annual revenue loss from stockouts, concentrated in 12% of SKUs

Planning team spending 70% of time managing exceptions rather than improving forecasts

No incorporation of external signals: weather, social trends, competitor pricing

Replenishment orders generated manually from spreadsheets — no automation

Our Approach

We built a three-model forecasting system. A base ARIMA model handles stable SKUs. A gradient boosting model handles volatile SKUs and incorporates external signals. A cold-start model uses category analogs for new product launches. All three feed an ensemble layer that picks the best forecast per SKU. Predictions go straight to the client's SAP ERP via API, triggering automated replenishment orders.

01

5-year historical sales data audit and cleaning — identified and corrected systematic data quality issues in 3 regional data warehouses

02

External signal integration: weather API, Google Trends, competitor pricing scraper, regional event calendar

03

Three-model architecture: ARIMA (stable), gradient boosting (volatile + external signals), cold-start analog model (new SKUs)

04

Ensemble layer that weights model outputs based on SKU category, velocity, and recency

05

SAP ERP integration — automated replenishment order generation from forecast outputs

06

Planner dashboard showing forecast vs actuals, model confidence, and override interface for exceptional items

Implementation Timeline
5 weeks
Data Audit & Integration
5-year data quality auditRegional warehouse consolidationExternal signal sourcingERP integration assessment
8 weeks
Model Development
Base model developmentExternal signal modelCold-start modelEnsemble architecture
4 weeks
Validation
Backtesting against historical actualsRegional accuracy analysisPlanner review and calibrationERP integration testing
3 weeks
Deployment & Optimization
Phased store rolloutPlanner trainingAutomated replenishment activationPerformance monitoring
Results & Impact

Twelve months after deployment, forecast accuracy improved from 61% to 94% across the covered SKUs. Stockout revenue loss dropped by $4M. The planning team's exception management time fell from 70% to 25% of capacity. They now focus on strategic range planning instead of chasing errors.

Forecast accuracy: 61% → 94% across 15,000 SKUs

$4M annual stockout revenue loss eliminated

Planner exception time: 70% → 25% of capacity

New product launch accuracy improved 2.8× through cold-start analog modeling

Automated replenishment covering 87% of SKUs — manual intervention only for strategic items

Our supply chain is now genuinely predictive. We stopped chasing stockouts and started preventing them. The ROI was clear within the first quarter.

RT

Rebecca Thorn

VP Supply Chain, National Retail Group

Client identity is withheld under NDA. The figures reported here were verified against the client's own internal reporting at project close.

Key Learnings

External signals gave the biggest accuracy boost on seasonal products. But that only worked after fixing the underlying data quality issues.

The cold-start model for new products turned out to be more valuable than anyone expected. New launch stockouts were the most painful and visible problem.

Giving planners an override interface with a clear rationale for each forecast accelerated adoption significantly.

Key Results

Accuracy Improvement3.2×
Stockout Cost Eliminated$4M
Forecast Accuracy94%
Stores Covered340

Technology Stack

Prophetscikit-learnLightGBMSnowflakeApache AirflowSAP ERP

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