The P/S ratio — when is Price-to-Sales useful? The formula, a worked example and three pitfalls

The P/S ratio — Price-to-Sales — is calculated as the company's market capitalization divided by its annual revenue, and it is at its most useful when earnings are negative, small or temporarily distorted: in other words, exactly where P/E has stopped working. A company with a market capitalization of 6 000 million kronor and revenue of 2 400 million has P/S = 2,5. The question the financial ratio asks is simple — what is the market paying per earned krona of sales? But the number says nothing about how much of that krona becomes profit, and that is where both the strength and the trap lie.

The formula — revenue is line 1, earnings are an afterthought

P/S = Market capitalization ÷ Net revenue

Equivalent form, stock by stock: P/S = Share price ÷ Revenue per stock. Market capitalization is, of course, the number of stocks multiplied by the current price. Net revenue is the top line of the income statement — revenue after customer discounts, returns and VAT, before a single cost has been deducted.

One practice question worth the habit: calculate on rolling twelve-month revenue (the last four quarters, LTM) instead of the latest full year. The latest fiscal year can be almost a year old when you read it, and for a company growing 30 % per year the difference between the two numbers is a quarter of a year's revenue. The second practice question: P/S is calculated on market capitalization and ignores debt. The variant EV/S — enterprise value divided by revenue — puts net debt in the numerator and gives cleaner comparisons between differently indebted companies. For two companies with equally solid balance sheets the choice matters little; just do not mix systematically.

The worked example: same P/S, two different business models

Imagine two hypothetical companies:

• Company A — a cloud service. Market capitalization 6 000 Mkr, rolling revenue 2 400 Mkr. P/S = 6 000 ÷ 2 400 = 2,5. Gross margin: 80 %.
• Company B — a retail chain. Market capitalization 3 000 Mkr, rolling revenue 3 000 Mkr. P/S = 3 000 ÷ 3 000 = 1,0. Gross margin: 25 %.

B looks on paper like half as expensive. But follow each revenue krona down the income statement: of A's krona, 80 öre are kept to cover product development, sales and ultimately profit. Of B's krona, 25 öre are kept — which moreover must carry stores, inventory and logistics before anything at all becomes earnings. A multiple per revenue krona can only be compared between companies whose kronor are worth roughly the same. That is why 0,5 in groceries and 5,0 in software is no paradox — it is the price of the gross margin.

Complete with a third angle: if A grows 30 % per year and B 3 %, the worlds differ even more, since a multiple on today's revenue in fact pays for future revenue. A rule of thumb that holds the reasoning together: a high gross margin carries a high P/S; a low gross margin requires either a very low P/S or high growth. In the AKM1 model this is exactly why V04 (P/S) is never read alone but always together with V01 (revenue growth) and V07 (gross margin) — three variables, one picture.

When P/S is at its most useful

Three situations make the multiple the first choice:

1. Early growth companies with negative results. When earnings are minus there is no P/E to calculate — division by a negative number is meaningless. Revenue is always there, on line 1, in black and white. 2. Temporarily distorted profits. Large depreciations, restructuring costs or a one-off sale can knock out earnings for a year without saying anything about the business itself. Revenue is the stable number underneath. 3. Cyclical companies in the middle of a trough. In a recession, earnings can fall 60 % while revenue falls 10 %. P/E then looks bizarrely high exactly when the stock exchange is at its most depressed — P/S gives a more stable reference point for where in the cycle the multiple sits.

Pitfall 1: revenue is not the same as revenue quality

The accounting rules (IFRS 15) distinguish between acting as principal — reporting revenue gross — and as agent — reporting one's fee. Two marketplaces with identical volume can therefore report entirely different revenue depending on legal structure and contract form. Read the note on revenue recognition before P/S is compared between companies: the same number can measure different things.

Pitfall 2: the trap of the low multiple

A P/S of 0,3 can be expensive. In structurally low-margin industries — trade, construction, staffing — margins are squeezed further in hard years, and a company traded at 0,3 × revenue with pressed profitability can look cheap until the losses have begun eating the equity. A low P/S without margin analysis is half an analysis. The IT bubble's mirrored lesson is the same story in reverse order: in 1995–2000, revenue growth without a credible path to profitability was valued at astronomical multiples, and when the capital drought came the revenue remained but the companies were gone. The multiple shouted expensive the whole way — what was missing was the question of what the kronor were worth.

Pitfall 3: revenue growth that has been bought

Discounts, aggressive sign-up offers and purchases of revenue through acquisitions can inflate line 1 without creating corresponding value. The check: follow the gross margin and the cash flow from operations as revenue grows. Growth bought at a loss shows up in the two numbers long before it shows up in the multiple.

The industry interpretation — the multiple has no zero point

Descriptively, with no yardstick beyond the comparison group: software companies with gross margins around 75–85 % have historically traded at multiples that would have made Graham raise his eyebrows — often several times revenue — while retail chains with margins around 20–30 % move around fractions of revenue. Commodity and service companies with thin margins often sit below 0,5. None of these levels is cheap or expensive in itself — they are the image of the gross margin. That is why P/S is a comparison measure within industries and a nonsense detector between them: the question is never whether 2,5 is a lot, but whether 2,5 is a lot for a company with this margin structure and this growth rate. A practical rule of thumb from the SaaS world is Rule of 40 — ARR growth plus EBITDA margin should together exceed 40 — and it works for the same reason: it weighs together the multiple's two drivers, growth and profitability, in a single number.

The exercise: calculate P/S on a real company

1. Look up market capitalization and rolling twelve-month revenue for a company you follow. 2. Calculate P/S on today's numbers — and backwards for the three most recent fiscal years. Is the multiple rising or falling, and does the course of events depend on the price or on revenue? 3. Look up the gross margin and compare the placement against the industry median in the calculator. 4. Place the three numbers — P/S, growth, margin — side by side and formulate in one sentence what the multiple is paying for.

Fifteen minutes, three numbers — and you know what the figure on the screen actually measures.

Next steps

• Deepen the multiple in the course P/S (V04): six chapters — chapter after chapter — on when Price-to-Sales carries the analysis and when it is just decoration.
• See how V04 is bound to the nineteen other variables in the Curriculum — valuation without margin is half-finished work.
• Test the whole in the portfolio builder: P/S is one voice in the choir, never the soloist.

FAQ

What is the P/S ratio?

P/S-talet (Price-to-Sales) är bolagets börsvärde delat med nettoomsättningen — ekvivalent aktiekurs delat med omsättning per aktie. Frågan är vad marknaden betalar per intjänad försäljningskrona; ett börsvärde på 6 000 Mkr mot en omsättning på 2 400 Mkr ger P/S = 2,5.

When is the P/S ratio useful?

När vinsten är negativ, liten eller tillfälligt förvrängd — alltså precis där P/E slutat fungera. Det gäller tidiga tillväxtbolag utan vinst, bolag vars resultat slagits ut ett år av engångskostnader, och cykliska bolag mitt i en svacka där omsättningen fallit mycket mindre än vinsten.

Why do software companies have a higher P/S than retail companies?

En multiplic per omsättningskrona kan bara jämföras mellan bolag vars kronor är värda ungefär lika mycket — bruttomarginalen sätter priset. I postens exempel behåller molntjänsten 80 öre av varje omsättningskrona mot detaljhandelskedjans 25 öre, så P/S 2,5 mot 1,0 är ingen paradox; en låg P/S utan marginalanalys är en halv analys.

This is educational financial analysis, not investment advice.