Data table A discussion with Madeline Avell, the controller, brings to light two possible explanations. She informs you that the industry gross profit percent in the retail drug industry declined fairly steadily for three years, which accounts for part of the decline. A second factor was the declining percent of the total volume resulting from the pharmacy part of the business. The pharmacy sales represent the most profitable portion of the business, yet the competition from discount drugstores prevents it from expanding as fast as the nondrug items such as magazines, candy, and many other items sold. Avell feels strongly that these two factors are the cause of the More info Your comparison of the gross margin percent for Jamberson Drugs for the years 2016 through 2019 indicates a significant decline. This is shown by the following information: Click the icon to view the data and additional discussion with the controller.) The following additional information is obtained from independent sources and the client's records as a means of investigating the controller's explanations: (Click the icon to view the additional information.) Requirement a. Evaluate the explanation provided by Avell. Show calculations to support your conclusions. Begin by computing the gross margin percentage for drug and nondrug sales for 2019 through 2016. (Round your answers to the nearest tenth percent, XX.X\%.)