Consumer Intelligence Research Partners (CIRP) is out with a new report today claiming Apple is now at over 100 million iPhones in use in the US. That means Apple has crossed 100 million active iPhone units since CIRP reported 97 million iPhones in use back in August, according to the research firm’s data.

CIRP uses its data to estimate that, of the 101 million iPhone in use during the quarter, around 58 million were iPhone 6 and 6 Plus, 4 million were iPhone 6s or 6s Plus, and the rest previous generation models (as pictured above).

The report’s data accounts for up to the end of the September quarter and notes that 101 million iPhones were in use according to CIRP’s data. The company gets its numbers “by analyzing data on iPhone buyers, their new model selection, and their prior phones, and overlaying Apple iPhone sales data adjusted to the US market…” A survey of 500 Apple customers to be specific. 

CIRP also offered some insight on growth of the iPhone’s installed base, which it notes shows “Apple has fewer first time smartphone buyers to add to their base, and faces the challenge of attracting loyal Android users”:

This installed base grew on average 8% per quarter for the past eight quarters. In the September 2015 quarter, the installed base grew 4%, compared to 6% in the September 2014 quarter… “The data again shows that growth in the installed base of iPhones in the US has slowed,” said Josh Lowitz, Partner and Co-Founder of CIRP. “In previous quarters, we saw the installed base grow by as much as 17%, in the December 2013 quarter after the launch of the iPhone 5S and 5C. As the US market matures, Apple has fewer first time smartphone buyers to add to their base, and faces the challenge of attracting loyal Android users.”

It was back in 2011 that Apple first announced it had reached the 100 million iPhones sold milestone, while in January it confirmed it had officially crossed its one billionth iOS device sold. Apple doesn’t, however, offer numbers on active iPhones in use.