from wikipedia
Costco Wholesale Corporation (NASDAQ: COST) is the largest membership warehouse club chain in the world based on sales volume, headquartered in Issaquah, Washington, United States,[1] with its flagship warehouse in nearby Seattle.[2] Costco’s Canadian operations are based in Ottawa, Ontario.[3] It is the fourth biggest general retailer in the United States, after Wal-Mart, The Home Depot, and Kroger.

