Domino’s Pizza Inc. shares slipped after the company reported a smaller-than-expected increase in comparable sales, citing growing competition and economic challenges.

Shares slumped as much as 4.8% in premarket trading in New York. Domino’s US same‑store sales climbed 0.9% in the fourth quarter, according to a statement Monday, less than the 2.5% increase expected by analysts surveyed by Bloomberg. Those projections had already been lowered from roughly 3.1% at the end of March.