The latest research from Consumer Intelligence Research Partners indicates the iPhone U.S. installed base reached 193 million units as of March 30, 2019, compared to 189 million units at the end of the December 2018 quarter and 173 million units at the end of the March 2018 quarter.
CIRP bases this estimate on an estimated global sales of 39 million iPhones, which is in turn derived from an estimated average selling price of $803 and Apple-disclosed iPhone revenues.
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As of March 30, 2019, the installed base grew 2% relative to the December 2018 prior quarter and 12% relative to the year-ago March 2019 quarter, according to the research group. One year ago, the iPhone U.S. installed base grew 4% over the prior quarter and 19% over the prior year.
“The US installed base of iPhones continues to plateau,” says Josh Lowitz, CIRP partner and co-founder. “Relative to the most recent quarters, and especially to the past two or three years, slowing unit sales and longer ownership periods means that the growth in the number of US iPhones has flattened considerably. Of course, 12% growth in a year, after years of much greater growth is still good. However, investors grew accustomed to quarterly growth of 5% or more, and annual growth of almost 20%. This continuing trend prompts investors to wonder if iPhone sales outside of the US will compensate, and places greater pressure on Apple’s determination to sell other products and services to the installed base of iPhone owners.”
CIRP bases its findings on its survey of 500 U.S Apple customers, surveyed from March 31, 2019 – April 11, 2019 that purchased an iPhone, iPad, or Mac in the U.S. in the January-March 2019 period.