Shares of Costco Wholesale Corporation ( COST ) rose 3% following the comparable-store sales results for April, the four weeks ended May 4, 2014 that bettered analysts' expectations. Excluding the effect of gasoline prices and foreign currency fluctuations, Costco's comparable-store sales for the period jumped 5%. Excluding the effect of inflation in gasoline prices and impact of foreign currency fluctuations, Costco's comparable-store sales for April rose 5%, reflecting comparable sales growth of 5% at its U.S. locations and 7% at international outlets.