📖 杜邦分析（DuPont Analysis）

Financial Statement Analysis

I. Lesson Focus

II. The Problem

Imagine you are comparing two listed companies in the same industry: Company A reports an ROE of 18% while Company B reports only 9%. At first glance, A appears superior. However, if A’s high ROE is primarily driven by extremely high financial leverage (debt ratio of 75%), whereas B achieves its results through strong net profit margins and superior asset turnover, which company is more sustainable in a downturn with rising interest rates? DuPont Analysis solves this by breaking the single ROE metric into “Net Profit Margin × Asset Turnover × Equity Multiplier,” allowing analysts to see the true drivers behind ROE and avoid being misled by headline numbers. It is one of the most important integrative tools in CFA Level I Financial Statement Analysis.

III. The Basic DuPont Framework

DuPont Analysis was developed by the DuPont Corporation in the early 20th century. Its core decomposes Return on Equity (ROE) into three key drivers:

$$ \text{ROE} = \text{Net Profit Margin} \times \text{Asset Turnover} \times \text{Equity Multiplier} $$

where: - Net Profit Margin = Net Income / Revenue — measures profitability - Asset Turnover = Revenue / Average Total Assets — measures operational efficiency - Equity Multiplier = Average Total Assets / Average Shareholders’ Equity — measures financial leverage

Multiplying the three components yields ROE = Net Income / Average Shareholders’ Equity.

This decomposition enables analysts to answer: “Is the high ROE due to high margins, fast turnover, or simply high borrowing?”

IV. The Five-Factor (Extended) DuPont Analysis

CFA Level I also requires mastery of the five-factor DuPont model, which further decomposes the net profit margin:

$$ \text{ROE} = \left( \frac{\text{EBT}}{\text{EBIT}} \right) \times \left( \frac{\text{EBIT}}{\text{Revenue}} \right) \times \left( \frac{\text{Revenue}}{\text{Average Total Assets}} \right) \times \left( \frac{\text{Average Total Assets}}{\text{Average Equity}} \right) \times (1 - \text{Tax Rate}) $$

Equivalently expressed as: - Tax Burden = Net Income / Pretax Income = 1 – effective tax rate - Interest Burden = Pretax Income / EBIT - EBIT Margin - Asset Turnover - Equity Multiplier

The five-factor model isolates the separate effects of taxes, interest, and operating profitability.

V. Relationship Between ROA and Leverage

From the DuPont identity we derive: $$ \text{ROA} = \text{Net Profit Margin} \times \text{Asset Turnover} $$ $$ \text{ROE} = \text{ROA} \times \text{Equity Multiplier} $$

Because Equity Multiplier = 1 + Debt/Equity, higher leverage amplifies ROE relative to ROA, but also increases risk.

VI. Practical Application and Comparative Analysis

The real power of DuPont Analysis lies in trend analysis across time periods and peer comparison. By decomposing ROE, analysts can determine whether an increase in ROE stems from genuine operating improvements or merely higher leverage, thereby assessing sustainability. DuPont decomposition is an indispensable diagnostic step in equity valuation and credit analysis.

Worked Cases

Case 1: Basic Three-Factor Decomposition

Company Jia reports the following 2023 figures (in CNY 10,000): - Net income = 1,200 - Revenue = 10,000 - Average total assets = 8,000 - Average equity = 4,000

Calculate ROE and perform the DuPont decomposition.

Solution: Net profit margin = 1,200 / 10,000 = 12%
Asset turnover = 10,000 / 8,000 = 1.25×
Equity multiplier = 8,000 / 4,000 = 2.0
ROE = 12% × 1.25 × 2.0 = 30%

Conclusion: Of the 30% ROE, leverage contributes the largest portion (2.0×), followed by turnover; profitability is moderate.

Case 2: Five-Factor Decomposition and Peer Comparison

Companies Yi and Bing operate in the retail sector. 2023 data (in CNY millions):

Yi: Revenue = 500, EBIT = 80, EBT = 65, Net income = 48, Avg. assets = 300, Avg. equity = 150
Bing: Revenue = 800, EBIT = 96, EBT = 88, Net income = 70, Avg. assets = 400, Avg. equity = 200

Compute ROE for both and compare.

Solution: Company Yi:
Tax burden = 48/65 ≈ 73.85%
Interest burden = 65/80 = 81.25%
EBIT margin = 80/500 = 16%
Asset turnover = 500/300 ≈ 1.667×
Equity multiplier = 300/150 = 2.0
ROE ≈ 73.85% × 81.25% × 16% × 1.667 × 2.0 ≈ 32.0%

Company Bing:
Tax burden = 70/88 ≈ 79.55%
Interest burden = 88/96 ≈ 91.67%
EBIT margin = 96/800 = 12%
Asset turnover = 800/400 = 2.0×
Equity multiplier = 400/200 = 2.0
ROE ≈ 79.55% × 91.67% × 12% × 2.0 × 2.0 ≈ 35.0%

Conclusion: Bing achieves a higher ROE mainly through superior asset turnover and lower interest burden despite a lower EBIT margin. Yi has stronger operating profitability but ends up with a lower overall return after leverage effects.

Case 3: Trend Analysis and Leverage Risk

Company Ding’s ROE rose from 15% to 18% to 22% over three years, while its debt-to-assets ratio increased from 45% to 68%. Use DuPont Analysis to assess the sustainability of the ROE improvement.

Simplified data (in CNY 10,000): - 2021: NI=600, Rev=4,000, Assets=5,000, Equity=2,750 → ROE=21.8% - 2022: NI=720, Rev=4,500, Assets=6,000, Equity=2,400 → ROE=30.0% - 2023: NI=850, Rev=4,800, Assets=7,500, Equity=2,400 → ROE=35.4%

Decomposition shows: net margin improved modestly (15% → 15.1% → 17.7%), asset turnover deteriorated (0.8 → 0.75 → 0.64), while the equity multiplier surged (1.82 → 2.5 → 3.125).

Conclusion: The ROE increase is primarily leverage-driven while operational efficiency declined, significantly elevating risk. Should interest rates rise or profitability weaken, ROE could collapse rapidly. This is a classic “leverage-driven ROE growth” trap.

Traps

Key Formulas

• ROE = Net Profit Margin × Asset Turnover × Equity Multiplier
• ROE = (Net Income / Revenue) × (Revenue / Avg. Total Assets) × (Avg. Total Assets / Avg. Equity)
• ROA = Net Profit Margin × Asset Turnover
• ROE = ROA × Equity Multiplier
• Five-factor ROE = Tax Burden × Interest Burden × EBIT Margin × Asset Turnover × Equity Multiplier
• Equity Multiplier = 1 + Debt/Equity
• Sustainable growth rate g = ROE × (1 – Dividend Payout Ratio)

Practice Questions

Q1. In the three-factor DuPont model, which component directly measures financial leverage?
A. Net profit margin
B. Asset turnover
C. Equity multiplier
D. Tax burden

Q2. A company has ROE of 15% and ROA of 10%. Its equity multiplier is:
A. 0.67
B. 1.5
C. 2.5
D. Cannot be calculated

Q3. In the five-factor DuPont model, “interest burden” equals:
A. EBIT / Revenue
B. EBT / EBIT
C. Net income / EBT
D. 1 – tax rate

Q4. A firm has a net profit margin of 12%, asset turnover of 1.2×, and equity multiplier of 2.5. Its ROE is:
A. 15%
B. 30%
C. 36%
D. 45%

Q5. Compared with the three-factor model, the main advantage of the five-factor DuPont analysis is that it:
A. Distinguishes the effects of operating profit, interest, and taxes
B. Is simpler to calculate
C. Does not require balance-sheet data
D. Directly calculates the sustainable growth rate

Q6. If a company borrows heavily to repurchase shares, which change is most likely?
A. Asset turnover rises and ROE falls
B. Equity multiplier rises and ROE rises (assuming ROA unchanged)
C. Net profit margin must rise
D. ROA must rise

Q7. Which situation most strongly suggests that ROE growth is unsustainable?
A. Rising net margin, stable asset turnover, declining equity multiplier
B. Stable net margin, declining asset turnover, sharply rising equity multiplier
C. All three factors rising moderately
D. Declining tax burden and rising EBIT margin

Q8. Company Yi has average total assets of CNY 800 million, average equity of CNY 200 million, and net income of CNY 120 million. Its ROE and ROA are respectively:
A. ROE = 60%, ROA = 15%
B. ROE = 15%, ROA = 60%
C. ROE = 60%, ROA = 60%
D. ROE = 15%, ROA = 15%

Answers

Takeaways

• DuPont Analysis decomposes ROE into profitability, efficiency, and leverage drivers
• Core three-factor formula: ROE = Net margin × Asset turnover × Equity multiplier
• Five-factor model further separates tax, interest, and operating effects
• ROE = ROA × Equity multiplier; leverage amplifies returns but also risk
• Always analyze ROE in conjunction with trends and peers; high ROE alone does not imply high quality
• CFA exams strictly require average assets and average equity; avoid year-end values