The growth in unlimited data plans from U.S. wireless carriers is leading to less consumption of WiFi in the country, according to a recent analysis.

OpenSignal, which analyzed a 90-day period beginning on Dec. 1, 2017, found that the time spent on WiFi dropped for three of the four major U.S. carriers compared to the first quarter of 2017.

Verizon saw its share of time spent using WiFi fall from 54 percent to 51 percent, while AT&T’s share slid from 52 percent to 49 percent. T-Mobile, which was already the lowest at 43 percent in early 2017, declined to 41 percent at the end of the year and into 2018.

Sprint, the nation’s No. 4 carrier, saw its share of WiFi usage remain steady at 51 percent.

OpenSignal analyst Peter Boyland noted in a blog post that the timing of the declines roughly coincided with all four operators vying for market share with new or updated unlimited plans.

“As unlimited data plans in the U.S. become more ubiquitous, customers appear less concerned about finding a ‘free’ WiFi connection, leaning more on their ‘unlimited’ 3G and 4G networks for connectivity,” Boyland wrote.

Increased network demand from unlimited customers had affected network speeds in recent years, but OpenSignal found that Verizon and AT&T stemmed those declines in its latest U.S. State of Mobile Networks report.

Boyland added although wireless customer habits appear to be changing, WiFi itself remains an important component of the market. He wrote that users of smartphones, which are more common than PCs or other devices in many developing markets, still spend nearly two-thirds of their time connected to WiFi in some countries.

“‘Multi-play’ operators who offer both mobile and fixed-line services must consider their WiFi coverage as part of their cellular network strategy, particularly as they move to converting home hubs into public hotspots,” Boyland wrote.