The stock fell 3% in after-hours trading on Monday.
Adjusted profit in the quarter was 6 cents a share, ahead of analysts' forecasts of 3 cents, while revenue of $124.3 million beat estimates of $119.1 million. Same-store sales rose 2.3% in the fourth quarter. Analysts had expected same-store sales to decline 1.8%.
Shake Shack said it expects revenue in 2019 of $570 million to $576 million, and sales of more than $700 million in 2020. Analysts were calling for revenue in 2019 of $575.5 million, and revenue in 2020 of $720.5 million.
The company said it expects same-store sales to range from flat to an increase of 1% in 2019 vs. analysts' forecasts of a 0.8% gain.
Tara Comonte, the company's finance chief, said on an earnings call with analysts that the company's forecast reflects continued declines in customer visits and slightly higher prices, The Wall Street Journal reported.
To boost sales, Shake Shack has joined with third-party vendors to offer delivery services, and added self-serve kiosks to more quickly handle orders.