Most American homes don’t have a landline telephone according to newly published figures. Young adults and renters are the most likely to be cell-phone only.

The figures come from the National Center for Health Statistics. Twice a year it carries out a wide-ranging survey of around 20,000 households on health issues and asks for a phone number in case staff need to follow up or double-check answers. Since 2003 it has also asked whether anyone in the house has a working cellphone and whether the household has a working phone line.

Back in 2003 barely a couple of percent of homes were cellphone only. That’s risen steadily and the new figures for the second half of 2016 showed they were in the majority for the first time. The survey showed 50.8 percent of homes only had cellphones, with a further 3.3 percent having no form of telephone at all.

As you might expect, demographic factors played a big role. Some of the groups with the highest proportion of people living in cellphone-only homes were people aged 25-29 (72.2 percent), people who lived with roommates rather than family (83.7 percent) and people who rented their property (71.5 percent). Of course, those three characteristics are likely to be highly correlated with one another.

The BBC noted that the figure is likely to be higher in the US than many countries because broadband provision is dominated by cable companies, meaning there’s often little need to have a landline solely for Internet access.

The trend has some effects beyond being a boost for cellphone manufacturers and service providers (and the resulting political questions of whether cellphone companies should be regulated to the same degree as fixed-line phone companies.) Because automated ‘robocalls’ are – theoretically at least – banned on cellphones, opinion pollsters who use them as a cheap option are now excluding the majority of the population from their potential respondents. That makes getting a representative sample more difficult given the significant demographic differences between the landline haves and have nots.