2.2 Activity (Efficiency) Ratios

What Activity Ratios Measure

Activity ratios (also called efficiency or turnover ratios) show how effectively a firm converts its assets into sales and cash. They pair a turnover figure (how many times an item cycles per year) with a days figure (how many days one cycle takes). The two are reciprocals scaled by 365: a higher turnover always means fewer days, and vice versa.

Use average balances (beginning + ending, divided by 2) whenever both period-end values are available; this smooths seasonal swings and matches a flow figure (annual sales or COGS) against a typical balance rather than a single point-in-time snapshot. The CMA exam will sometimes give only an ending balance, in which case you use that figure directly, but prefer the average when the data allows.

Receivables, Inventory, and Payables

• Receivables turnover = net credit sales / average accounts receivable. How many times receivables are collected per year.
• Days sales outstanding (DSO) = 365 / receivables turnover. Average days to collect.
• Inventory turnover = cost of goods sold (COGS) / average inventory. How many times inventory sells through.
• Days inventory outstanding (DIO) = 365 / inventory turnover. Average days inventory sits before sale.
• Payables turnover = purchases (or COGS) / average accounts payable.
• Days payable outstanding (DPO) = 365 / payables turnover. Average days the firm takes to pay suppliers.

DSO and DIO are costs of doing business: cash locked in customers and shelves. DPO is a source of free financing: the longer you defer payment, the more supplier credit funds operations.

Asset Turnover

• Total asset turnover = net sales / average total assets. Revenue generated per dollar of assets.
• Fixed asset turnover = net sales / average net fixed assets (property, plant, and equipment). Efficiency of long-term productive assets.

A total asset turnover of 1.5x means every $1 of assets produces $1.50 of sales. Capital-intensive industries (utilities, manufacturing) run low turnover; retailers and service firms run high. Compare only within an industry.

Why turnover matters for returns: total asset turnover is one of the three DuPont drivers of return on equity (covered in Section 2.3). A firm that cannot lift its margins can still raise returns by squeezing more sales out of the same asset base, which is exactly what activity ratios measure. Falling turnover with steady sales is an early warning that assets, especially receivables and inventory, are bloating.

The Cash Conversion Cycle

The cash conversion cycle (CCC) measures the number of days between paying for inventory and collecting cash from the resulting sale:

CCC = DSO + DIO - DPO

A shorter (or even negative) cycle is better because less cash is tied up in operations. A negative CCC means suppliers effectively finance the firm's entire operating cycle, a hallmark of strong retailers and platforms.

Full Worked Example: CCC

Assume for the year: net credit sales $1,460; COGS $1,095; purchases $1,000; average receivables $200; average inventory $150; average payables $125.

CCC = 50 + 50 - 45.6 = 54.4 days.

Interpretation: it takes about 54 days from the moment cash leaves to pay suppliers until cash returns from customers. To shorten the cycle, the firm can speed collections (lower DSO), sell inventory faster (lower DIO), or negotiate longer supplier terms (higher DPO).

Trap: Stretching DPO too far damages supplier relationships and may forfeit early-payment discounts worth far more than the financing benefit. Reducing DSO too aggressively (tight credit) can shrink sales.

Two Related Measures

The operating cycle = DSO + DIO. It measures the total time from acquiring inventory to collecting the cash from its sale, before considering supplier financing. The cash conversion cycle then subtracts DPO to net out the days suppliers fund the firm.

In the worked example above, the operating cycle is 50 + 50 = 100 days, and the CCC of 54.4 days is shorter because suppliers finance roughly 46 of those days. A firm with a negative CCC (common for large retailers) collects from customers before it must pay suppliers, generating cash from growth instead of consuming it.

Exam tip: Watch the signs. DSO and DIO are added (cash tied up); DPO is subtracted (cash provided). Reversing a sign is the most common arithmetic error on CCC questions.

Linking Activity Ratios to Working-Capital Strategy

Activity ratios are not academic; they translate directly into cash needs. Each day shaved off the cash conversion cycle frees cash that would otherwise be borrowed or raised from owners.

Estimating the cash impact: if daily cost of sales is roughly $3,000 (COGS of $1,095 divided by 365), then cutting DIO by 10 days releases about $30,000 of cash previously locked in inventory. Multiply the change in days by the relevant daily flow (sales for DSO, COGS for DIO and DPO) to size the benefit.

Managers improve each lever differently:

• Lower DSO: tighten credit terms, offer early-payment discounts, automate collections.
• Lower DIO: adopt just-in-time inventory, improve demand forecasting, discontinue slow movers.
• Raise DPO: negotiate longer supplier terms, but only when no discount is forfeited.

Trap: Improving one ratio can hurt another. Tighter credit lowers DSO but may reduce sales and turnover; leaner inventory lowers DIO but risks stockouts. The exam rewards recognizing these trade-offs, not just memorizing formulas.