Stock in Costco dropped Thursday as its same-store sales fell short of expectations, a rare miss for the warehouse club owner that highlights how strong sales of groceries aren’t enough to make up for weakness in other areas.

Costco Wholesale (ticker: COST) said comparable sales were up 4.3% for the four weeks ended Nov. 27, while core sales, which exclude fluctuations in currency and fuel, were 5.3% higher. Its U.S. locations recorded the weakest core growth, at 4.6%, while e-commerce sales were down 8.9% from the year-ago period.

Source: finance.yahoo.com