Buffett's 1991 letter: Debt, valuation and Keynesian wisdom

There is something deeply grounding about reading Warren Buffett's annual letters. The 1991 one, in particular, feels like a calm voice in a market that never stops yelling. While Wall Street was busy chasing fads and fiddling with spreadsheets, Buffett was doing what he always does: focusing on businesses, not tickers; people, not projections; and logic, not labels.

In this part of our ongoing series on Buffett's annual letters, we see him sharpen old lessons and challenge new illusions. Whether it's about how to truly value a media company, the difference between a franchise and a business, or the proper way to think about debt, this letter is packed with insights that still hold firm in today's noisy world.

Look-through earnings: See the business, not the ticker

Buffett called for readjusting the lens. Instead of peering at stock quotes, he urges investors to look through the holdings in their portfolios and tally up the earnings they represent. Not market value. Not charts. Just the earnings attributable to each share owned.

This essentially entails thinking of your portfolio as your own mini-conglomerate. Its worth? Not what the market says today but the stream of earnings it generates over the next decade. This perspective pushes you to ask the right questions: How durable is the business? Who is managing it? What happens to the profits? You start thinking like a business owner, not a stock trader.

It's a simple mindset shift but a powerful one. The below example shows how you can calculate your look-through earnings.

This Rs 35 crore represents your true share of profits from the three companies regardless of whether they were distributed as dividends. Over time, it's these retained earnings that quietly compound on your behalf, often more effectively than what you could do yourself.

Franchises vs businesses: A moat by another name

Buffett draws a sharp line between two types of companies: economic franchises and plain old businesses. Franchises sell products or services that are needed, have no close substitutes, and are not price-regulated. This trifecta allows them to raise prices, earn high returns, and survive even with mediocre management.

Businesses, on the other hand, thrive only if they are low-cost operators or benefit from temporary supply tightness. Their fortunes are far more fragile. A few bad managerial calls and the whole thing unravels.

What Buffett is getting at is this: Franchises come with moats. Businesses don't. And in a world where change is constant and competitors are relentless, moat matters.

Media's valuation math: When expectations shift, so does value

One of the more sobering sections of the 1991 letter is Buffett's commentary on the changing economics of media businesses. What once looked like perpetually growing annuities—TV stations, newspapers, and magazines—began to resemble the rest of the business world: cyclical, capital-hungry, and unpredictable.

Buffett illustrates this with a neat bit of valuation math. If you believed a media property could grow earnings at 6 per cent forever, using a 10 per cent discount rate, you could justify paying 25 times earnings. But if those same earnings are flat and cyclical? The multiple collapses to 10 times. The shift in narrative alone wipes out 60 per cent of the valuation.

This is not just about media. It's about how assumptions—about growth, capital needs, and stability—drive valuation. Change the assumptions, and the story changes completely.

A simple ratio for evaluating debt

Buffett offers a neat shortcut for sizing up a company's debt burden: debt divided by net profit. The result tells you how many years it would take to repay the debt if earnings remained constant.

It's not flashy. It won't show up in investment banking presentations. But it tells you what you need to know.

See's Candy Shops: Evaluation of a franchise

See's remains one of Buffett's favourite case studies and with good reason. From 1972 to 1991, the business required just $18 million in incremental capital to generate $410 million in pre-tax profits. That is about $23 of profit for every $1 reinvested. Try beating that in a spreadsheet.

What makes See's extraordinary is not just the return on capital, it's how little capital it actually needed. Buffett bought a brand, a customer experience, and pricing power, not a factory. And that made all the difference.

Understand what you are investing in

Finally, Buffett returns to one of his foundational beliefs: don't diversify for the sake of diversification. Look for a few great businesses run by exceptional people, buy them at sensible prices, and hang on. No portfolio full of mediocrities. No flavour-of-the-month rotation. Just a handful of enterprises you understand and trust.

He ends the letter with a quote from Keynes that sums it well: "It is a mistake to think that one limits one's risk by spreading too much between enterprises about which one knows little and has no reason for special confidence."

Conclusion

As ever, Buffett's message is one of simplicity and discipline. Look through the portfolio to see what you actually own. Prioritise moats over momentum. And when you find a great business run by great people, don't let go too easily.

The 1991 letter reminds us that investing is not about being clever but clear. Clear about value, clear about expectations, and clear about the kind of companies worth holding for decades. The scoreboard may track market prices, but the game is still won on business performance. And that is something the market will never outgrow.

Also read: The one thing to make you rich (No, it isn't high returns)

This article was originally published on April 07, 2025.