Build a product profitability dashboard for a fashion e-commerce business.

The dashboard should include:
1. Net profit overview by product and category.
2. Comparison of revenue vs net profit to highlight high-revenue, low-profit products.
3. Net profit breakdown by size to surface size-related return risks.
4. A list or table of products with consistently negative net profit.
5. Reference expected margin rates from the product cost structure data where available.

The goal is to help a business owner decide:
- Which products to keep or optimize
- Which sizes cause disproportionate losses
- Where pricing or cost adjustments are needed