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Inventory Turnover & Days (DSI/DIO)

Evaluate how quickly inventory is sold and converted into cash flow.

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Direct costs of producing products sold during the period

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Valuation of stock at start of measurement window

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Valuation of unsold stock at year close

Supply Chain Velocity

A higher turnover ratio means products sell rapidly, minimizing holding costs and reducing stock obsolescence risk.

Results

Inventory Turnover Ratio
8.00x
Days Sales of Inventory (DSI / DIO)46 Days
Average Inventory Maintained₹1,00,000
Annual Stock Cycles8.0 Cycles / Year
Turnover VelocityBalanced

Key component of the Cash Conversion Cycle (CCC).

How Inventory Turnover & DSI (DIO) Are Calculated

Inventory turnover measures the operational velocity at which a business sells through and replenishes its stock over an accounting period. Rather than measuring sales revenue—which includes distortive gross profit markups—turnover compares the actual cost of merchandise cleared against the average capital tied up in warehouses.

Step 1: Average Inventory
Avg Inv = (Beg Inv + End Inv) ÷ 2

Smooths seasonal fluctuations between opening and closing warehouse balances.

Step 2: Turnover Ratio
Turnover = COGS ÷ Avg Inv

Indicates how many times inventory is completely cleared and restocked annually.

Step 3: Days Sales (DSI/DIO)
DSI = 365 ÷ Turnover Ratio

Expresses inventory holding duration in calendar days before being converted to sales.

Worked Example: Baseline Inventory Velocity Analysis

Consider an enterprise with annual Cost of Goods Sold of ₹8,00,000, beginning inventory of ₹1,20,000, and ending inventory of ₹80,000:

Calculation MetricFormula / InputValueOperational Interpretation
Cost of Goods Sold (COGS)User Input₹8,00,000Total direct manufacturing/purchasing cost of goods sold.
Beginning InventoryBalance Sheet (Jan 1)₹1,20,000Warehouse valuation at start of reporting period.
Ending InventoryBalance Sheet (Dec 31)₹80,000Physical count valuation at close of fiscal year.
Average Inventory Maintained(₹1,20,000 + ₹80,000) ÷ 2₹1,00,000Working capital tied up in stock across the year.
Inventory Turnover Ratio₹8,00,000 ÷ ₹1,00,0008.00xThe company clears and turns over its inventory 8 times annually.
Days Sales of Inventory (DSI / DIO)365 ÷ 8.0045.6 Days (~46 Days)Goods sit in the warehouse for 46 days before being converted to sales.

Industry Turnover & DSI Benchmarks

  • Grocery & Supermarkets: 14x – 22x turnover (16–26 days DSI). Perishable goods demand rapid stock velocity to avoid spoilage.
  • Consumer Electronics: 6x – 10x turnover (36–60 days DSI). Fast technology lifecycles necessitate tight inventory controls against depreciation.
  • Apparel & Fashion Retail: 4x – 6x turnover (60–90 days DSI). Driven by seasonal fashion lines; excess inventory triggers markdown discounting.
  • Automotive & Heavy Industrial Machinery: 2x – 4x turnover (90–180 days DSI). High unit cost and specialized manufacturing allow longer holding windows.

The "High Turnover Trap" vs. Sluggish Stock

While high turnover is generally praised, extremes reveal operational friction:

  • Danger of Overly High Turnover (>25x): Frequent stockouts, unfulfilled customer orders, missed bulk supplier discounts, and high freight expediting fees.
  • Danger of Low Turnover (<3x): High carrying costs (insurance, warehousing, security = 15–25% of stock value), dead stock write-downs, and tied-up cash flow.
  • Impact on CCC: DSI is Days Inventory Outstanding (DIO). Every day shaved off DSI directly accelerates cash flow in the Cash Conversion Cycle (DIO + DSO − DPO).

Assumptions & Analytical Limitations

  • Two-Point Average Distortion: Using only beginning and ending balances can skew ratios if a business experiences seasonal peaks (e.g., Diwali or holiday stocking) or intentionally dumps stock prior to fiscal year-end. Monthly 12-point averages provide superior accuracy.
  • Inventory Valuation Rule (FIFO vs. Weighted Average): Under inflation, FIFO produces a higher ending inventory and slightly lower turnover ratio than Weighted Average costing. (LIFO is prohibited under IFRS and Indian AS 2).
  • Product-Mix Aggregation: Blended turnover can mask critical operational imbalances where top-selling items turn 30 times a year while obsolete SKUs linger on shelves for 400 days without moving.
Optimizing inventory order sizes and holding costs?Read our supply chain guide on Economic Order Quantity (EOQ): Balancing Ordering vs. Carrying Costs Without Running Out of Stock to align inventory turnover with batch replenishment economics.

Frequently asked questions

What is a good inventory turnover ratio?
Fast-moving consumer goods (FMCG) and grocery retailers typically turn over inventory 12 to 20 times per year (DSI of 18–30 days). Luxury retailers and heavy machinery manufacturers may turn inventory only 2 to 4 times per year (DSI of 90–180 days).
Why use COGS instead of Sales Revenue?
Inventory is valued at historical cost on the balance sheet. Using Sales Revenue would artificially inflate the turnover ratio with gross profit markups, creating an apples-to-oranges comparison. COGS accurately measures cost-to-cost.
What is the relationship between Inventory Turnover and DSI (DIO)?
Days Sales of Inventory (DSI, also known as Days Inventory Outstanding or DIO) is the inverse of the turnover ratio expressed in days: DSI = 365 / Inventory Turnover Ratio. A higher turnover ratio yields a shorter DSI.
Can an inventory turnover ratio be too high?
Yes. An excessively high inventory turnover ratio may indicate inadequate stock levels, frequent stockouts, lost sales opportunities, or excessive freight costs from rushed replenishment orders.
How does inventory turnover affect cash flow and working capital?
Higher inventory turnover shortens the Cash Conversion Cycle (CCC), freeing up tied-up working capital, reducing holding and storage expenses, and lowering the risk of product obsolescence.

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Inventory Turnover Ratio

8.00x