Methodology: Online Store RU only. For each SKU/brand, the discount is split into two effects: (1) Subsidy — revenue given away on units that would have sold at full price anyway (baseline avg units × discount%); (2) Incremental gain — revenue from genuinely new demand driven by the discount (extra units × discounted price). Efficiency = Incremental gain ÷ Subsidy. Break-even uplift = minimum extra units/day needed for the discount to pay for itself = baseline_qty × discount% ÷ (1 − discount%).

Methodology: Calculated exclusively on Online Store RU data. For each product, average daily retail revenue is derived from in-stock days (Out of Stock and NA days are excluded from the base). NA days are excluded from both the base and lost-sales count. Lost Revenue = avg daily revenue × number of Out of Stock days.

Lift Analysis: For each placement, average daily sales N days before and N days after are compared. Lift = (sales_after − sales_before) / sales_before × 100%. CTR = clicks / views. ROI = (revenue_after − revenue_before − cost) / cost × 100%.