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Ledgerwise

The decision simulator

simulator

How would I actually behave in a crash?

Twenty years of real market history with the dates hidden. You allocate each year, then find out what your decisions cost against simply holding.

How it works

  1. 1. You start with $100,000 and add $5,000 a year.
  2. 2. Each round is one year of real market history. You choose an allocation before seeing what happens.
  3. 3. The years are hidden. You see only what an investor at the time would have seen.
  4. 4. At the end you are scored against a passive 60/35/5 portfolio held through the same 20 years.

You already know to buy and hold. The question is whether you will.

The best-measured finding in retail investing is that investors earn less than the funds they own — not because the funds are bad, but because of when people buy and sell. Reading that changes nothing. Watching it happen to you might.

This is not a test of whether you can call markets. It is an experiment on your own reactions to a drawdown you cannot date, run against sequences that actually happened — including the ones no model would generate.

What this measures

At the end you get one number: the gap between what your decisions produced and what simply holding would have produced. That is the behaviour gap, measured on you rather than described to you.

If you beat the benchmark, take it seriously but not too seriously — one favourable sequence out of ninety-odd possible starting points is exactly the sample size that convinces people they have a talent.