DuPont Analysis

DuPont analysis is an identity, not a model: each factor introduces a term that cancels against the next, leaving net income over equity untouched. Multiply net income divided by revenue by revenue divided by total assets and revenue cancels, giving return on assets. Multiply that by total assets divided by shareholders' equity and assets cancel, restoring return on equity. Because the relationship holds by construction, it can never be wrong; its value lies entirely in attribution, in showing which component moved.

Consistency matters more than convention. Income statement figures cover a period while balance sheet figures are point-in-time, so most analysts use average total assets and average equity to align the two. Whichever choice is made, apply it to every factor and to every period being compared, otherwise the product of the components will not reconcile to the headline return.

The five-part version breaks the net profit margin into three ratios that separate operating performance from financing and taxation. Net income divided by pre-tax income measures the tax burden, the proportion of pre-tax profit retained after tax. Pre-tax income divided by EBIT measures the interest burden, the proportion of operating profit surviving interest expense. EBIT divided by revenue is the operating margin, the cleanest available measure of core profitability before capital structure and jurisdiction distort it.

Multiplying tax burden by interest burden by EBIT margin reproduces the net margin exactly; appending asset turnover and the equity multiplier reproduces return on equity. The payoff is diagnostic: a firm that levers up raises its equity multiplier but simultaneously depresses its interest burden ratio, and the five-part form makes that trade-off visible instead of hiding it inside a single margin figure.

Different industries reach comparable returns through structurally different factor combinations. Branded pharmaceutical and software firms generate high operating margins on slow-turning asset bases; distributors and grocers invert that profile. Regulated utilities combine modest margins and very low turnover with substantial leverage, while banks operate with equity multipliers an order of magnitude above those of industrial firms, which is why their returns must be assessed against risk-weighted capital rather than the multiplier alone.

The decomposition is equally useful across time and across peers. A year-on-year fall in the equity multiplier accompanied by a stable EBIT margin points to deleveraging rather than operating deterioration. Conversely, an expanding multiplier alongside a deteriorating interest burden and flat operating margin signals that the return is being manufactured by the balance sheet. Rising asset turnover may reflect genuine efficiency, or asset sales, impairments, sale-and-leaseback transactions and heavy depreciation shrinking the denominator.

Candidates should be able to construct any version of the decomposition from a raw income statement and balance sheet, move fluently between the two-, three- and five-factor forms, and back out a missing component when the others and the return on equity are supplied. Expect items that provide two firms' factor sets and ask which driver explains the difference in their returns, or that give two periods and ask whether the change originated in operations, efficiency or financing.

The interpretive skill is knowing what each factor cannot tell you. The equity multiplier captures financial leverage but says nothing about off-balance-sheet obligations or debt maturity. Asset turnover is sensitive to accounting choices in asset recognition and to the age of the asset base. The tax burden ratio reflects statutory rates, geographic mix and one-off items alike, so a single favourable year is not evidence of a durable advantage.