Costco Wholesale Corporation ( COST ) posted its comparable-store sales (comps) results for the five weeks ended Jan 4, 2015 that fared better than analysts' expectations. Excluding the effect of deflation in gasoline prices and the impact of foreign currency fluctuations, Costco's comps for Dec 2014 rose 8%, reflecting an equivalent increase across its U.S. locations and international outlets. Coming to Costco, comps for the 18-week period increased 4%, buoyed by a 6% rise at its U.S. locations.