What happened

Shares of FedEx (NYSE:FDX) were down 4.9% as of 2 p.m. EDT on Tuesday after the courier delivery services giant announced mixed results for the 2019 fiscal first quarter.
More specifically, FedEx's quarterly revenue climbed 11.8% year over year to $17.1 billion, which translated to adjusted (non-GAAP) earnings of $3.46 per diluted share, up from $2.51 in the year-ago period. But analysts, on average, were modeling higher EPS of $3.82 on lower revenue of $16.9 billion.
Stock market data with a red line chart indicating losses
IMAGE SOURCE: GETTY IMAGES.

So what

CFO Alan Graf Jr. said: "As expected, the quarter's results were affected by our decision to invest in our team members following the passage of the Tax Cuts and Jobs Act. We remain committed to increasing earnings, margins, cash flows, and returns this year."
Meanwhile, CEO Frederick Smith credited the company's earnings growth to the "solid execution of our business plan and a strong U.S. economy," adding that FedEx is "very optimistic" about its ability to drive profitable growth going forward.
During the subsequent conference call, management also noted that while shipments between the U.S. and China represent just 2% of total revenue, the potential for new tariffs is affecting the market and could mean moderated economic growth going forward.

Now what

Nonetheless, FedEx reaffirmed its previous full-fiscal-year 2019 guidance for revenue growth of roughly 9%, while at the same time increasing its outlook for adjusted EPS in the range of $17.20 to $17.80 (up from $17 to $17.60 previously). 
With that in mind, it seems the broader market is unjustly punishing FedEx stock today in response to its bottom-line shortfall relative to expectations and, to a lesser extent, the potential for tariffs to hurt its business. Though with shares up 18% in the year leading up to this report, perhaps the news was enough to tempt some to take profits on any hint of weakness.