A high turnover ratio indicates strong sales or lean stock management; a low ratio warns of overstocking, obsolescence or weak demand. The inverse — Days Inventory Outstanding (DIO) — expresses the same idea in days of supply.
Benchmarks vary widely: a supermarket may turn inventory 15–25 times a year, a fashion retailer 4–8 times, a luxury watchmaker once. Aiming for an industry-appropriate level balances availability against working capital cost and write-off risk.
Inventory Turnover = COGS ÷ Average Inventory
A retailer with CHF 2m COGS and average inventory of CHF 250,000 turns inventory 8 times per year, or roughly every 46 days.