Costco notches 9.9% sales gain in December

Costco Wholesale Corp. COST, +0.57% on Thursday said that December sales rose 9.9% year over year to $26.15 billion, helped by a jump in its e-commerce business, with sales for the 17 weeks ending Dec. 31 coming in at $82.86 billion, a 5.9% gain. The membership retail chain said that in December, same-store sales overall rose 8.5%, with a 5.2% increase for those 17 weeks. E-commerce sales in December were up 17.7%. Shares rose 0.8% after hours. ...