For each of the past two years, major department stores have reported a nearly 50% increase in their sales of men's clothing manufactured by Zachary, Inc., a result that is all the more surprising because the sales of most other brands of men's clothing have been depressed over the same period. Nevertheless, even Zachary, Inc. does not appear to have emerged unscathed from the overall trend: despite the aforementioned increase, Zachary, Inc. has reported a slight decline in overall sales in each of the past two years.

Which of the following, if true, most helps to explain the surprising result above?