Inventory Forecasting Model for Seasonal E-commerce Businesses

Build an inventory forecasting model for [STORE NAME], a [NICHE] e-commerce store with [NUMBER] SKUs and [NUMBER] months of sales history.\\\\\\\\n\\\\\\\\n**Data Requirements:**\\\\\\\\n- Historical sales data: [NUMBER] months by SKU\\\\\\\\n- Seasonality patterns: monthly/weekly/daily\\\\\\\\n- Lead times by supplier\\\\\\\\n- Planned promotions and marketing events\\\\\\\\n- Growth rate trend\\\\\\\\n- Stockout history (when items were unavailable)\\\\\\\\n\\\\\\\\n**Forecasting Method:**\\\\\\\\n\\\\\\\\n1) **Baseline Demand:**\\\\\\\\n- Moving average (3-month) for stable products\\\\\\\\n- Exponential smoothing for trending products\\\\\\\\n- Seasonal decomposition for seasonal products\\\\\\\\n\\\\\\\\n2) **Seasonality Adjustment:**\\\\\\\\n- Seasonal index per month (based on historical data)\\\\\\\\n- Special event multipliers (Black Friday, holidays, etc.)\\\\\\\\n- Day-of-week patterns\\\\\\\\n\\\\\\\\n3) **Promotion Impact:**\\\\\\\\n- Historical lift from past promotions\\\\\\\\n- Planned promotion calendar\\\\\\\\n- Estimated demand increase per promotion type\\\\\\\\n\\\\\\\\n4) **Safety Stock Calculation:**\\\\\\\\n\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\nSafety Stock = Z × σ_demand × √(lead_time)\\\\\\\\nWhere:\\\\\\\\n- Z = service level factor (1.65 for 95%, 2.33 for 99%)\\\\\\\\n- σ_demand = standard deviation of demand during lead time\\\\\\\\n- lead_time = average supplier lead time in days\\\\\\\\n\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\n\\\\\\\\n5) **Reorder Point:**\\\\\\\\n\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\nReorder Point = (Average Daily Demand × Lead Time) + Safety Stock\\\\\\\\n\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\\\\\\\\\\\\\\\\`\\\\\\\\n\\\\\\\\n**Output — Purchase Recommendations:**\\\\\\\\nFor each SKU:\\\\\\\\n- Current stock level\\\\\\\\n- Forecasted demand (next 30/60/90 days)\\\\\\\\n- Reorder point and recommended order quantity\\\\\\\\n- Urgency flag (critical/soon/ok)\\\\\\\\n- Estimated stockout date if not reordered\\\\\\\\n\\\\\\\\n**Dashboard:**\\\\\\\\n- Inventory health overview\\\\\\\\n- SKUs at risk of stockout\\\\\\\\n- Overstock alerts\\\\\\\\n- Supplier performance (lead time accuracy)\\\\\\\\n- Forecast accuracy tracking (MAPE)\\\\\\\\n\\\\\\\\nInclude forecasting spreadsheet model with formulas and a purchase recommendation report template.