Popular investing rules, tested on real data from dozens of markets.

Each test asks one question: would following the rule have beaten simply holding the index, after costs?

Latest tests

Last updated Nov 11, 2026

A beach umbrella and lounger on an empty beach under a clear summer sky

Sell in May and go away: does it still work?

The pattern is real in most countries, but sitting in cash all summer still earned less than buy-and-hold.

Nov 11, 2026 · 41 markets · 1928–2026