A question often asked by new investors is: "How much can I make in the stock market?" It’s a perfectly good question, but both simple and difficult to answer.

The simple answer might lie in a very long chart of any major stock market index you choose, placed on a log plot, which is used to deal neatly with the issue of compounding. This is useful because stock indices tend to compound their returns over time — and so does inflation, the No 1 problem most sensible investors try to contend with...