User:Wb26-NJITWILL

Within the section of the costco article entitled “membership” the writer explains in the definition of Costco’s membership and I quote “American Express is the only accepted credit card (in the United States, Canada, and Japan) because they charge Costco very low interchange fees (a percentage of revenue from total sales made); as Costco's margins are low in comparison to other retailers ”. As a student majoring in mathematics of finance I do agree with the statement that a credit card company would charge the warehouse low interchange fee due to total sales made being very high, on the other hand, mentioning that Costco’s margins are low compared to other retailers without citation would be pure speculation. The reasoning of the writer is correct but without proper citation the statement becomes invalid. With proper reliable sources of citation to back up these statements it would be accepted otherwise it would have to be changed according to what the facts found show the standing of the company compared to other retailers.