“Over time, the share of iPhone buyers that come from the Android operating system has varied seasonally, yet remained relatively consistent,” said Josh Lowitz, CIRP Partner and Co-Founder.
But remember, these are U.S. numbers.
“It appears,” concludes CIRP’s Mike Levin, “that Apple enjoyed a much higher rate of Android switching outside the U.S. than in the more mature U.S. market.”
That seems reasonable. And it jibes with the news coming of out China, where Canalys reports that Apple overtook Xiaomi, Samsung, and Huawei last quarter to take the top spot in smartphone sales.
Follow Philip Elmer-DeWitt on Twitter at @philiped. Read his Apple AAPL coverage at fortune.com/ped or subscribe via his RSS feed.