The company's shares fell as much as 4.3% to $9.75 in premarket trading on Wednesday. Restaurants have not to been able to keep prices low, despite a fall in food costs, as they struggle to comply with minimum-wage increases. This has led a host of chains, including McDonald's Corp (MCD), Dunkin' Brands Group Inc (DNKN) and Starbucks Corp (SBUX), to post disappointing same-restaurant sales for the quarter. Sales at Wendy's restaurants open for at least 15 months rose 0.4% in North America, missing the 1.9% rise analysts polled by research firm Consensus Metrix had expected. Total sales fell 22% to $382.7 million as the company franchised more outlets, but beat the average analysts' estimate of $367.6 million, according to Thomson Reuters I/B/E/S. Wendy's (WEN) said it operated 361 fewer restaurants at the end of the second quarter. The company sold 55 of them to franchisees out of the 315 it aims to refranchise by 2016.