A note on the impacts of JIT on the financial ratios of a manufacturing firm: for advanced management accounting students

A note on the impacts of JIT on the financial ratios of a manufacturing firm: for advanced management accounting students (related to seminar exercise q3)

 

Regarding the topic of Just-in-time (JIT) practice in manufacturing management, discuss in general the JIT impacts of the manufacturing companies with regard to some of the financial ratios.

Just-in-Time (JIT) generally improves manufacturing companies’ activity, profitability, and cash-flow ratios by reducing inventory, waste, cycle time, and operating costs. However, it can lower conventional liquidity ratios because current assets—especially inventory—fall.

Core financial effects

Financial ratio	Typical JIT impact	Why it happens
Inventory turnover	Improves	Lower raw-material, work-in-process, and finished-goods inventory means the same cost of goods sold is supported by much less inventory.
Days inventory outstanding / inventory-to-assets	Improves / falls	JIT produces or buys items only when needed, reducing capital tied up in stock.
Working-capital turnover	Improves	Lower inventory and receivables reduce net working capital, so sales generated per dollar of working capital rise.
Current ratio	May decline	Current assets fall when inventory is reduced; this is not necessarily bad if cash conversion and operating efficiency improve.
Quick ratio	May decline or remain stable	The numerator loses inventory, although stronger operating cash flow can offset this.
Gross and operating margins	Often improve	Less waste, scrap, handling, storage, obsolescence, and downtime reduce cost of sales and operating expenses.
Return on assets (ROA) / ROI	Often improve	Lower asset base—especially inventory—and higher margins increase returns generated from assets.
Return on sales (ROS)	Often improve	Cost reductions and better quality can raise operating profit relative to sales.
Cash ratio / operating cash flow	Often improve	Cash formerly invested in inventory is released for operations and supplier transactions.
Debt ratios / leverage	May improve indirectly	Less need to finance inventory can reduce borrowing, although firms may still hold cash or invest elsewhere.

Activity ratios

The clearest JIT effect is on inventory turnover:

Inventory turnover = Cost of goods sold / Average inventory

If a manufacturer cuts average inventory from $10 million to $4 million while maintaining cost of goods sold at $40 million, turnover rises from 4.0 to 10.0 times per year. This means inventory is converted into sales much faster, reducing holding costs, spoilage, obsolescence, and warehouse requirements.

JIT also improves working-capital turnover:

Working-capital turnover = Net sales / Net working capital

Because JIT reduces current assets more than it reduces current liabilities, working capital can fall; if sales remain stable or rise, turnover improves. A study of JIT/ TQM manufacturers found statistically significant improvements in inventory turnover and working-capital turnover after adoption.

Profitability ratios

JIT can raise profitability through several channels:

• Lower purchasing and production waste, defects, rework, and quality-related costs. 
• Shorter production cycles and faster delivery, supporting higher throughput and customer service.
• Lower inventory carrying costs, including storage, insurance, handling, and obsolescence. 
• Better labor and equipment productivity because problems become visible quickly when buffers are removed.

Empirical research on 253 U.S. manufacturers found significant relationships between the extent of JIT practices and profitability measures, supporting the view that sustained JIT implementation can improve financial performance. Other evidence links JIT adoption with higher ROA, ROS, asset turnover, earnings, and EPS.

Liquidity ratios

JIT creates an important apparent paradox: it may reduce the current ratio even while improving financial health.

Current ratio = Current assets / Current liabilities

Because inventory is a major component of current assets, JIT reduces the numerator. The CPA Journal reported that current and quick ratios declined significantly after JIT/TQM adoption, while inventory and working-capital turnover improved. Therefore, managers should interpret liquidity ratios alongside cash-flow and turnover measures rather than treating a lower current ratio as automatically negative.

Cash flow and capital structure

By converting inventory into cash, JIT can improve operating cash flow and increase the cash-to-assets ratio. Research on JIT adoption finds that firms shift resources from inventory into cash, with higher cash ratios, healthier operating cash flows, and lower leverage ratios reported among JIT adopters.  

This can strengthen financial flexibility: the firm needs less short-term financing to carry inventory and can respond more quickly to supplier payments, investment opportunities, or demand changes.

Important caveat

JIT’s ratio benefits depend on a reliable supply chain, stable demand, high-quality suppliers, flexible production, and disciplined quality control. If suppliers fail, transport is disrupted, or demand spikes, very low inventory can cause production stoppages, lost sales, expedited freight costs, and margin erosion.

In short, JIT usually makes a manufacturer look more efficient and profitable—especially through inventory turnover, ROA, margins, and cash flow—but it may make traditional liquidity ratios look weaker because inventory is deliberately minimized.