This bull market’s strongest gains are behind us. That is the conclusion that I reached after analysing all US bull markets since 1900.

The good news is that, assuming the future is like the past, the current trend still has months of life in store. The bad news is that the stock market’s gains during those months are likely to be more modest than what we have been used to, which suggests that we should not extrapolate the gains of the past 12 months.