Evidence & sources
Where the industry figures come from
The levers of the model calculation are aligned with published studies and case reports. Every third-party figure named in the text is documented here with its source.
- McKinsey: AI forecasts reduce errors by 20-50%; markdown optimisation improves markdown margin by 400-800 basis points.
- BoF State of Fashion 2025: full-price sell-through down to ~50%.
- IHL: ~8% revenue loss from out-of-stock.
- Fit Analytics (Mammut): -20% return rate through size guidance.
- True Fit/M&Co: -10% among active users.
- University of Bamberg returns research: ~€19.51 process cost per return; German fashion returns ~50%.
- Prime AI: value loss of 20-40% of merchandise value.
- Heuritech (vendor claim): trend forecasts up to 24 months ahead, 90%+ - we deliberately assume 6-9 months and 67%.
- Pareto norm: ~20% of SKUs carry ~80% of revenue.
- Inditex FY2024: gross margin ~58% (context: initial markup).
The figures of other companies serve as plausibility anchors - they are not transferred to the model company. All EUR amounts are model calculations based on the assumptions stated in the disclaimer. Retrieval date of the sources: 2026-08-14.
Note on the context of this portfolio
The following six modules use a fictitious mid-sized fashion company (jeans, T-shirts, hoodies, shirts) to illustrate how data science and AI can be applied across the entire value chain - from pre-order to trend identification to markdown optimisation.
All figures, datasets and results are entirely fictitious. They serve solely to illustrate the methodology and the type of impact achievable - no promises made.
In a real project, the domain expertise of your company is the decisive factor: how does your pre-order process work? What data is available in your PLM, ERP and webshop? Where are the biggest losses - overstock, returns or missed trends? On this basis we develop models tailored to your reality.
This portfolio shows what questions data science can answer in the fashion industry - the concrete answers emerge only with your data.