A share is a small piece of a real company with real customers and profits.
Own a business, not a ticker.
Two shares, the same chart. Tap the one to own.
The chart was the same. The business under it decided everything.
← Red LinesRed Line 31 of 48 The idea The numbers Where you see it Where it bends This game’s numbersHow strong the proof isBGood proof, with limits Where it comes from
Behind every ticker is a company that sells things, pays people and makes a profit. Each share is a slice of that profit. Over the years, the price follows the business.
A company earns €1 a share and the share costs €20: twenty times its profit. Ten years later it earns €2. At the same twenty times, the share is about €40.
Day to day, prices bounce on mood. Over a decade, the companies whose profits grew are the ones whose shares rose.
A broad index fund is a piece of every business at once, which is fine: you own the profits of thousands.
Worked out on this page
Over long spans, share returns follow the companies’ profits and dividends, but over months and years prices drift far from them.
- Stock Prices, Earnings, and Expected Dividends John Y. Campbell & Robert J. Shiller, The Journal of Finance 43(3), 661-676, 1988
- Triumph of the Optimists: 101 Years of Global Investment Returns Elroy Dimson, Paul Marsh & Mike Staunton, Princeton University Press, 2002
Checked 2 Nov 2026 · How we grade
- A Strong proof: Many good studies or long official data, from different teams or countries, point the same way.
- B Good proof, with limits: Solid studies agree on the direction, but the size varies, or the data covers few places or few kinds of people.
- C Mixed proof: Some good studies for, some against, or the evidence covers only part of the line.
- D Thin proof: Mostly one book’s argument, one survey or stories. It may be wise, but it has not been tested well.
- = True by the sums: It follows from arithmetic, so no study can overturn it. We still show what real data says.
Benjamin Graham, The Intelligent Investor (1949). In our words, not quoted.
See it in numbers: Shares · P/E (From Zero)
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