The Dow Transports are lagging. Here’s how that impacts stocks and the economy.

As the other major U.S. stock-market averages have soared to new all-time highs, the Dow Jones Transportation Average DJT has struggled.

The index as of March 4 was more than 6% below the all-time high it made back in November 2021 — 28 months ago. Over the past year, the Dow Transports has lagged the broader Dow Jones Industrial Average DJIA by more than 12 percentage points. The reason this has many investors worried is the belief that the transportation sector is a leading indicator of U.S. economic activity.

Yet…