Every December, Barron's, the weekly financial magazine, asks Wall Street strategists to pick the best and worst sectors to invest in, and every year their picks perform poorly relative to the unmanaged Standard & Poor's 500 index. 2017 was much the same.

The strategists include brilliant economists, but economists are not seers.

It's not uncommon for the consensus forecast of economists to fail to predict if the economy will expand or fall into a recession - a question with just two possible answers.