Experiment #3 – What does a 1% difference really cost over time?

A difference of 1% in investment returns doesn’t sound like much.

But the 1 percent difference in investment returns can have a dramatic impact when compounded over decades.

It’s a small number.

But over time, small differences can compound in unexpected ways.

Which leads to a simple question:

What does a 1% difference actually mean in real terms?

This isn’t about predicting returns.

It’s simply a curiosity worth exploring.

Try This Small Experiment

Open ChatGPT, Gemini or another language model.

Then paste the prompt below.

Please compare the following two scenarios:

£100,000 invested for 25 years at:

Please show:

• The final value in each scenario

• The difference in pounds

• A simple explanation of the difference

It only takes a few seconds.

This experiment turns a small percentage difference into a tangible outcome.

It helps illustrate how compounding works over time.

Sometimes the difference is larger than expected.

Sometimes it simply reinforces how long-term investing behaves.

Either outcome is useful.

The purpose of this experiment is not to suggest a “better” return.

It is to explore how small differences can shape long-term outcomes.

Because understanding compounding often changes how people think about money.

If this experiment sparked further curiosity, you may find the following useful:

• Evoa – a structured environment for exploring financial questions independently

• The Wealth Coach – if you prefer to discuss your thinking with someone experienced

You can also subscribe to Letters, where we regularly explore ideas about financial thinking and decision-making.

Financial Curiosity Project | Exploring better questions about money.