The trend to drop landlines has been growing over the last decade alongside the growth in mobile phone use, according to semi-annual surveys performed by the Centers for Disease Control, which wants to monitor how to contact people for future surveys. But it wasn’t until the end of 2016 that a majority of all households relied solely on mobile phones.

In the CDC survey for the second half of 2016, 50.8% of households had only mobile service, up from 48.3% a year earlier. Another 39.4% of households had both types of service and 6.5% had landlines only. The survey, released on Thursday, found 3.2% of homes had no phone connection of any kind. The CDC surveyed almost 20,000 households during the six-month period.

The trend follows the financial results seen at major telecommunications providers like AT&T (T) and Verizon (VZ), which have seen their revenue from landline phones sliding precipitously while wireless phone revenue has boomed—at least until the past year or so. Now, with more mobile phones lines than people in the country, that growth has also slowed.

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Many consumers may be dropping landline service as a cost-saving measure. A greater portion of adults living in poverty (66%) and near poverty (59%) were relying solely on cell phone service, the CDC said. Among higher income adults, only 49% were mobile-only.

The demise of landline phone service was the first example of cord cutting, when consumers dropped a wired product for a wireless alternative. Now, many consumers are also dropping cable TV service, in some cases for mobile video streaming apps on their phones. And a small but growing number of people appear to be dropping landline Internet service to rely solely on the mobile Internet.