During the fourth quarter of 2016, Apple’s iPhone 7 and 7 Plus accounted for 72% of all U.S. iPhone sales, according to data from research firm Consumer Intelligence Research Partners (CIRP). Just 15% of iPhone 7 and iPhone 7 Plus owners were previously Android users. The vast majority of iPhone 7 and iPhone 7 Plus buyers in the fourth quarter were previously iPhone owners.

“The new 7 and 7 Plus models attracted mostly loyal iPhone owners, rather than Android owners,” CIRP partner and co-founder Mike Levin said in a statement. “This continues the trend of new iPhone models attracting mostly repeat iPhone buyers.”

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CIRP didn’t estimate actual iPhone unit sales in the U.S. last quarter.

Apple (AAPL) released its iPhone 7 and 7 Plus in September. The iPhone 7 comes with a 4.7-inch screen, while the iPhone 7 Plus offers a 5.5-inch display. Both run on iOS 10 and come with improved processors and displays compared to 2015’s iPhone 6s line. The iPhone 7s are also the first from Apple not to come with a headphone jack.

Apple hasn’t announced iPhone 7 or iPhone 7 Plus sales, leaving analysts and market researchers to perform retail checks to estimate how many units the company has sold. CIRP’s data, for instance, is based on a survey of 500 U.S. Apple customers who purchased the company’s handset during the fourth quarter.

Determining how many iPhone 7 owners switched from Android is an important metric for Apple. The data provides insight into the iPhone’s stature in comparison to Android alternatives and provides a glimpse on how well Apple is doing at not only appealing to its existing customer base, but also those that have tried other devices and might consider an iPhone.

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According to CIRP, 14% of shoppers who bought an iPhone 6s in 2015 were formerly Android users, suggesting the iPhone 7 has done little to improve Apple’s standing with Android customers.

The CIRP data follows another report released this week from the research company that found Apple’s total share of smartphone activations in the U.S. last quarter hovered at 34%. It just barely topped Samsung, which nabbed 33% of smartphone activations. CIRP co-founder and partner Josh Lowitz said in a statement that the iPhone might have been held back by “a strong portfolio of competing Android phones introduced throughout 2016.”

Still, for Apple’s financials, the fourth quarter might have been a good one: more customers bought higher-priced iPhones than cheaper Apple handsets, like the iPhone SE.

“The entry level iPhone SE had a smaller share of sales than the similarly positioned 5S did a year ago, and the most expensive iPhone 7 Plus garnered a larger share than the 6S Plus did in the same quarter a year ago,” Lowitz said in a statement. “The shift to newer, more expensive phones suggests that Apple could see an uptick in average selling price for iPhones, at least based on US market dynamics.”