As Apple Distorts Stock Market Indices, So iPhone Sales Distort Retail Sales Figures

It has been noted that Apple's stock performance  has an outsize impact on the overall U.S. index. 

Now it is clear that sales of Apple iPhones also have an outsized effect on retail sales figures. In October 2011, when the iPhone 4S was launched, about half the increase in retail sales came from computers and software. 

On average, the last three iPhone debuts saw retail-sales growth of 0.81 percent compared to average expectations of 0.1 percent. The bad news is that it is an Apple artifact: it distorts the impact of the rest of the segment.