Shares of logistics giant FedEx (NYSE:FDX) have seen wild swings all of 2019, and these swings are continuing after the company’s latest earnings report on Sept. 17. FDX stock dropped sharply in after-hours trading on Tuesday and could slide further in the coming weeks.

Many market participants consider FedEx to be a good read on the global economy, given the company’s global logistics business. The company has been issuing cautious guidance at best for the past 12 months, and this cautious tone was reiterated in the company’s earnings call on Tuesday. Specifically, the CEO Frederick W. Smith cited global trade tensions as a concern over global growth.