These graphs illustrate the difference in pricing for simvastatin 20mg among retailers, as a percentage of Average Wholesale Price in March of 2007, and a year later, in March 2008. “Costco Wholesale” represents the approximate price Costco paid to manufacturers for the drug. (Source: “Why Generic Doesn’t Always Mean Cheap,” The Wall Street Journal, March 13, 2007 and www.drx.com.)