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, but 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 are 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, in 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.