Shake Shack Inc. said on Thursday that its same-store sales rose 17.1 percent in the third quarter ended September 30, continuing the burger chain’s strong sales showing following its January initial public offering.

Shake Shack has now raised its outlook for 2015 revenues to a range of $US189 million to $US190 million from $US171 million to $US174 million.

Revenue climbed 67 percent to $53.3 million in the quarter, topping analysts’ estimate of $47.3 million. “We opened four domestic company-operated Shacks during the quarter and, as previously announced, we will be officially opening our first Shack in Tokyo in the remarkable Meiji-Jingu Gaien park this November, ahead of schedule”.

Shares of TripAdvisor tumbled by as much as 4.7% to $79.20 per share in after-hours trades following tonight’s earnings report. And, same-store sales are now expected to grow by between 11% and 12% this year.

For 2016, Shake Shack forecast total revenue of $237 million to $242 million and same-restaurant sales growth of 2.5 percent to 3 percent.

TripAdvisor’s GAAP net income was 51 cents per share or $74 million, compared to last year’s 37 cents per share or $54 million. In constant currencies, click-based ad revenue would have increased by about 15%. Hotel segment revenue rose 8% to $340 million.

Net income in the quarter tripled to $1.5 million or 10 cents per share from $500,000 or 2 cents in the same period a year ago.

Critics worry that the chain’s explosive same-store sales growth, a gauge of restaurant performance, will fade as it expands beyond very dense urban areas.