Excluding the impact of foreign currency fluctuations and gasoline prices, Costco's comps for the month under review rose 2%. After reporting flat comparable-store sales (comps) in August, Costco Wholesale CorporationCOST has continued to post positive comps so far. We note that shares of Costco have climbed roughly 13.5% since Oct 5, 2016, when the company reported September sales results.