calculate_inventory_kpis
ChatGPTUse this when a seller or their accountant asks for inventory turnover or turns, days of inventory or days on hand (DSI), sell-through rate, gross margin return on inventory (GMROI), how fast stock is moving, or which products turn slowest. Do not use to decide which stock is dead or overstocked. Needs current stock with SKU, on hand and unit cost (an optional beginning on-hand column improves the average), plus sales lines with SKU, date and quantity; a price or line-total column in the sales file adds revenue and GMROI. Returns per-SKU and overall turnover (annualized from the sales period), days of inventory, sell-through, GMROI and stock value, flagging slow movers. Read-only; stores nothing.
