Module 2 · Market Instruments · Lesson 6
Debt
A tool or a trap, depending on the hand that holds it.
Quick Answer
How Do You Evaluate a Company’s Debt?
Evaluate a company’s debt by checking how much it owes, whether its earnings can comfortably cover interest payments and when the debt must be repaid. The main figures to review are the debt-to-equity ratio, interest coverage ratio, current and quick ratios, debt maturity schedule and credit rating. Debt can support growth, but excessive debt can make a company vulnerable during recessions or periods of higher interest rates.
Debt is the most misunderstood number on a balance sheet. Investors who do not understand it tend either to fear it irrationally or ignore it entirely — both of which lead to losses. A company with the right amount of debt is more profitable, more efficient, and faster-growing than one with none. A company with too much debt is one bad quarter away from disaster.
Debt is simply money the company has borrowed from banks, bond investors, or other lenders. In exchange, the company pays interest at a fixed or floating rate and must repay the principal at a future date. The borrowed funds let the business build factories, acquire competitors, or fund product development without diluting existing shareholders by issuing new stock. Used wisely, debt amplifies returns. Used recklessly, it amplifies losses.
The difference between a healthy debt load and a fatal one is rarely obvious in good times. It becomes obvious in bad times — and by then it is too late. This lesson covers the five debt metrics that separate solvent companies from precarious ones, the most famous case study in financial history (Lehman Brothers), and the rules Warren Buffett uses to dodge companies that look fine until they suddenly are not.
The same balance sheet looks completely different depending on what the borrowed money is doing. Apple holds tens of billions in debt because borrowing at 3 percent and earning 25 percent on the deployed capital is one of the best trades on Earth. A struggling retailer holding the same debt is one bad season from default. The number alone tells you almost nothing without context.
|
<20%
Buffett’s preferred debt-to-equity ceiling |
31:1
Lehman Brothers’ leverage in 2008 |
$619B
Largest bankruptcy in US history |
Sources. Berkshire Hathaway shareholder letters. Lehman Brothers Chapter 11 filing September 2008.
Part One
The idea in plain English
Debt can help a company grow, but too much debt reduces flexibility. The key question is whether the company can comfortably service its obligations in bad times.
How this looks in real investing
A stable utility may handle more debt than a cyclical retailer because its cash flows are more predictable.
What to avoid
Assuming all debt is bad or all debt is harmless. The quality of cash flow matters.
Do this before moving on
Check debt, interest expense and cash on hand before judging a company as safe.
The five debt metrics that matter
Hundreds of debt-related figures appear on a balance sheet. Five tell you everything that matters.
“Companies that have no debt can’t go bankrupt.”
— Peter Lynch
Part Two
Case study: Lehman Brothers, September 2008
The most famous debt-driven collapse in modern history offers the clearest lesson on leverage. Lehman Brothers had survived 158 years — wars, depressions, multiple recessions. It died in 48 hours because of one number: 31 to 1.
Case Study
How $25 billion in equity supported $691 billion in assets
Source. Lehman Brothers Chapter 11 filing September 15, 2008. Examiner’s report by Anton Valukas, March 2010.
Equity $25B 3.6% Total Liabilities $666B 96.4% Leverage ratio 31 : 1 Every 1% drop in asset values consumed 31% of shareholders’ equity A 3.6% loss = wipeoutThe math was lethal. Lehman held $691 billion in assets against just $25 billion of shareholders’ equity — a leverage ratio of 31 to 1. When the value of mortgage-backed securities (which made up a huge portion of those assets) fell by just 3 to 4 percent, Lehman’s entire equity base was theoretically gone. Counterparties knew this. They stopped lending. Without short-term funding, the firm could not meet daily obligations. It filed for bankruptcy on 15 September 2008 — the largest in US history.
The investors and analysts who held Lehman stock right up to the end were not unintelligent. They were trusting public financial statements that masked the true leverage through accounting techniques (notably “Repo 105”). The deeper lesson is not just to check the leverage ratio — it is to be sceptical of any business model that requires constant short-term funding to function. Banks and insurance companies live and die on confidence. When confidence falters, leverage is no longer a tool. It is a noose.
“When you combine ignorance and leverage, you get some pretty interesting results.”
— Warren Buffett
Part Three
How to evaluate any company’s debt in 10 minutes
Five quick checks. Every one is in the public filings.
Step 1
Find total debt
Step 2
Calculate D/E ratio
Step 3
Check coverage
Step 4
Look at maturities
Step 5
Compare to industry
One. Find total debt on the balance sheet. Add “Short-term debt” and “Long-term debt” (sometimes called “Borrowings”). Some companies also have operating lease liabilities — include those if they are material.
Two. Calculate the Debt-to-Equity ratio. Total debt ÷ Shareholders’ equity. Under 0.5 is conservative. 0.5–1.0 is normal. Over 2.0 is aggressive unless it is a financial institution or utility.
Three. Check interest coverage. EBIT ÷ Interest expense from the income statement. Above 4× is healthy. Below 2× is a red flag, even if everything else looks fine.
Four. Look at the debt maturity schedule. In the 10-K, find the table showing when debt principal repayments are due. A large maturity in the next 24 months is a refinancing risk. Spread maturities are safer than lumpy ones.
Five. Compare to industry peers. A 1.5× D/E ratio is high for a software company and normal for an industrial. Use the company’s competitors as the relevant baseline, not absolute thresholds.
Part Four
Where investors misread debt
Even careful investors get burned. Five recurring patterns.
Treating all debt as bad. Companies with zero debt may be inefficient. Capital structure has an optimal point — debt at low cost can dramatically improve return on equity. Reject a company because of too much debt; don’t reject one just because it has some.
Ignoring off-balance-sheet liabilities. Operating leases, pension obligations, and guarantees of subsidiaries often sit outside the headline debt number. A retailer with $5 billion in reported debt and $20 billion in operating lease commitments is closer to $25 billion in real debt. Read the footnotes.
Confusing low rates today with low rates forever. Companies that borrowed cheaply during the 2010s look fine on current interest coverage. Those same debts must eventually be refinanced — possibly at much higher rates. Project what the interest bill will look like if rates rise 3 percentage points.
| Mistake | Why It Hurts | Defence |
|---|---|---|
| Debt phobia | Reject good companies on principle | Look at coverage, not just absolute debt |
| Ignoring off-B/S liabilities | Real leverage hidden in notes | Always read footnotes |
| Assuming rates stay low | Surprise interest bills | Stress-test against +3% rates |
| Trusting “manageable” | Manageable in good times only | Stress-test against recession |
| Margin loans personally | Personal leverage amplifies losses | Avoid investing on borrowed money |
Trusting company descriptions of “manageable” debt. Every CFO calls the current debt level “manageable” until the day they file for bankruptcy. Make your own assessment from the numbers; never rely on management’s adjective.
Using personal margin loans to invest. The same warning applies to your own balance sheet. Borrowing to invest amplifies returns in good markets and amplifies wipeouts in bad ones. Most retail investors who use margin in their first decade lose materially more than non-margin investors over the same period. The math of leverage is symmetric, but the psychology of forced selling at a margin call is not.
“You really don’t need leverage in this world. If you’re smart, you’re going to make a lot of money without borrowing.”
— Warren Buffett
Investor Wisdom
What the great investors said about leverage
Ten quotes on borrowed money — the most powerful, most dangerous tool in finance.
“Companies that have no debt can’t go bankrupt.”
— Peter Lynch
Means. Solvency, ultimately, is about being able to meet obligations. No obligations means no insolvency risk.
Apply. In recession-prone industries, lean toward companies with little or no debt.
“You really don’t need leverage in this world. If you’re smart, you’re going to make a lot of money without borrowing.”
— Warren Buffett
Means. Patient compounding without borrowed money is plenty to reach financial freedom.
Apply. Resist margin loans. The math is symmetric; the psychology is not.
“When you combine ignorance and leverage, you get some pretty interesting results.”
— Warren Buffett
Means. Borrowing magnifies whatever you’re doing — including your mistakes.
Apply. Never use leverage on positions outside your Circle of Competence.
“I do not like to invest in companies that have too much debt, particularly long-term debt.”
— Warren Buffett
Means. Long-term debt + rising rates = profit destruction. The cash flow impact compounds.
Apply. Stress-test debt-heavy companies against a 3-point rise in rates.
“Pay off your debt first. Freedom from debt is worth more than any amount you can earn.”
— Mark Cuban
Means. Personally, high-interest debt costs more than markets typically return.
Apply. Pay off credit cards and personal loans before serious investing.
“It’s only when the tide goes out that you discover who’s been swimming naked.”
— Warren Buffett
Means. Highly-leveraged companies look fine until conditions tighten. Then they collapse.
Apply. Stress-test every holding against a recession scenario, not just a benign one.
“When purchasing depressed stocks in troubled companies, seek out the ones with the superior financial positions and avoid the ones with loads of bank debt.”
— Peter Lynch
Means. Two stocks down 60 percent — one with no debt recovers, one with lots dies.
Apply. In a market crash, sort opportunities by leverage. Low-debt names recover; high-debt names default.
“A banker who is allowed to borrow money at X and loan it out at X plus Y will just go crazy and do too much of it.”
— Charlie Munger
Means. Lending businesses systematically over-expand when conditions are easy.
Apply. Be suspicious of banks growing loans aggressively during boom times.
“Neither a borrower nor a lender be; for loan oft loses both itself and friend.”
— William Shakespeare, Hamlet
Means. The oldest debt advice still applies: borrowing changes relationships and concentrates risk.
Apply. Never lend or borrow socially. Keep money out of friendships.
“The four most dangerous words in investing are ‘this time it’s different’.”
— Sir John Templeton
Means. Every debt-driven crisis was preceded by analysts arguing the old leverage rules no longer applied.
Apply. Stick to debt rules through cycles, especially when the cycle convinces you it has been defeated.
Key Takeaways
Six things to take from this lesson
| 01 | Debt is a tool, not inherently good or bad. The same level can be healthy for one company and fatal for another. |
| 02 | Five metrics matter: D/E ratio, interest coverage, current/quick ratios, debt maturity profile, credit rating. |
| 03 | Buffett rejects companies with debt over 20% of equity or repayment longer than 2 years of net profit. |
| 04 | Lehman Brothers’ 31:1 leverage made a 3.6% asset drop a fatal event. Hidden leverage kills. |
| 05 | Off-balance-sheet liabilities, debt maturity walls, and rising-rate scenarios are where most surprises hide. |
| 06 | Personally, avoid margin loans. Compounding does the work; leverage adds risk that compounding cannot heal. |
Five Commitments
What you commit to before moving on
Read each one. If you cannot honestly commit to it, the lesson is not finished.
| I. | I will check D/E ratio and interest coverage for every individual stock I buy. |
| II. | I will read the debt footnote of every 10-K to find off-balance-sheet liabilities. |
| III. | I will stress-test high-debt holdings against a 3-percentage-point rate rise and a recession. |
| IV. | I will not use margin loans to amplify my investment exposure. |
| V. | I will pay off personal high-interest debts (credit cards, personal loans) before adding to risky investments. |
End of Lesson
Module 2 . Lesson 6 of 21 . Continue to Lesson 7 . Compound Interest.
Primary sources and further reading
Use these references to check the definitions, methods and risks discussed in this guide. Examples are for learning and do not predict investment results.
- SEC Investor.gov: How to Read a 10-K
- SEC Investor.gov: How to Read a 10-K or 10-Q
- FINRA: Bonds
- SEC Investor.gov: Using EDGAR to Research Investments
Education only. This guide provides general information, not personal investment, financial or tax advice. Check current rules and official filings before making a decision.
