Citi and Costco faced range of problems from delays in getting new cards to issues with automatic payments and long hold times for calls to customer service desks during the first few week after the cut over of American Express at the stores. Costco ( COST ) reported mixed Q4 fiscal 2016 earnings on Thursday, September 29. Although Costco's comparable sales growth for the fourth quarter was flat, it should be noted that a fall in gasoline prices and the strengthening dollar had a significant negative impact on the company's growth.