The randomness of global stock market returns

Investment opportunities exist all around the globe, but the randomness of global stock returns makes it exceedingly difficult to figure out which markets are likely to be outperformers. How should you deal with this kind of uncertainty?

First, you should remember that it’s challenging, at best, to predict a country’s returns by looking at the past, as shown by the performance of global markets since 2001 (see chart below). In the past 20 years, annual returns in 22 developed markets varied widely from year to year. (Each colour represents a different country, and each column is sorted top down, from the highest-performing country to the lowest.)

Two examples help make the point well:

• Austria posted the highest developed markets return in 2017—but the lowest the next year.

• The US ranked in the top five for annualised returns over the entire 20 years but finished first in the country rankings just once over that period. In nine calendar years, it was in the lower half of performers.

Why it doesn’t matter

As an investor, you can benefit from understanding that you don’t need to predict which countries will deliver the best returns during the next quarter, next year, or next five years. Why? Holding equities from markets around the world — as opposed to those of a few countries or just one, which I see too often when clients first come to see me — positions you to potentially capture higher returns where they appear, and outperformance in one market can help offset lower returns elsewhere.

Put another way, a globally diversified portfolio can help provide more reliable outcomes over time.