Stock-market investors scan these early recession indicators for signs the U.S. economy will crack. You should, too.

Seemingly every day, U.S. investors are being buffeted by a flurry of sometimes conflicting economic data.

Take this past week, for example: the U.S. leading economic index sank 1.2% in March, its biggest decline in three years. The indicator has now declined for 12 straight months.

Then, one day later on Friday, investors received readings…