stock markets

After a period when consensus ruled, economists are as much at odds today as they were in the 1980s, and policies can alter sharply when those in charge change. Quantitative easing is today the main bone of contention among policy makers and economists.  

The US seems expensive relative to other major stock markets. As it is probable that cheaper markets will give better returns, this implies that investors should underweight US equities. This conclusion applies, however, only over the longer term. Timing matters and this involves other considerations.

Chart one illustrates that G5 stock markets are strongly correlated with the US and so, to a large extent, markets go up and down together. The chart also shows that this tendency has been strengthening over time. 

The cyclically adjusted price-earnings ratio (Cape) has become well known as a way of valuing the US equity market. Its moderate success in this role has led to the assumption that the same approach will be valid for other markets. Unfortunately this seems doubtful, as I will try to explain. I should warn readers that, despite trying to make my explanation as simple as possible, I have been unable to avoid raising some quite technical points.

There are two fundamental and very different ways in which equity markets can be measured. One of these is q, by which the market value of companies is compared to the real value of their assets. This follows from the basic principle that, in any reasonably competitive economy, the value of anything depends on the cost of creating it — and it is therefore the macroeconomic approach. The other way treats equities as financial assets and values them by discounting the expected future returns at an appropriate rate. Cape is based on this approach and depends for its validity on the data for any particular stock market being consistent with the theory behind it.