This Economic Indicator Says to Tread Carefully

By Joel Litman

Editor's note: Today, we're breaking from our usual fare to cover one critical reason why it's time to be selective as an investor. In this piece, Joel Litman – founder of our corporate affiliate Altimetry – highlights an indicator you should be watching right now... And he reveals why it means many industries are already vulnerable.

The outlook isn't great for a lot of industries right now...

This week, the Institute for Supply Management ("ISM") announced its Purchasing Managers' Index ("PMI") rating for April. The index measures how strong manufacturing activity is in the U.S.

A PMI rating below 50 indicates economic activity is shrinking. April's rating was 47.1... And while that was better than expectations, it marked the fifth consecutive month of contraction.