The stock market’s return will be minus 3.3% a year over the next decade, says this ‘single greatest predictor’

This month we’ve received both good and bad news from the “single greatest predictor of future stock market returns.”

I’m referring to the indicator, first proposed by the Philosophical Economics blog in 2013, based on the average household’s portfolio allocation to equities. It is a contrarian indicator, with higher equity allocations associated with lower subsequent market returns, and vice versa.

The…