PORTLAND — Sunday, March 10, is National Landline Telephone Day, marking the date when Alexander Graham Bell made his first phone call in 1876.

The invention gradually became ubiquitous, and today we’ve all got phones in our pockets and purses. But for decades, phones hung on our kitchen wall or sat by a lamp in our living room, connected to one another with copper phone lines.

In 2000, right around their peak, Oregon had 1.5 million residential landlines, according to state data, more landlines than there were households.

Nearly everyone had a phone in their house and many people had more than one — with a separate line set aside for a fax machine, dial-up internet to America Online, or perhaps for the teenagers who spent all evening talking on the phone with their friends.

Now, federal data shows that slightly fewer than a third of Oregon homes have landline phones. That’s roughly the same share of U.S. homes with landlines.

Cell phones are more convenient and more capable, connecting us to the internet for news, movies, social networking and even the video calls Dick Tracy foretold.

It’s no wonder most people decided they don’t need to pay for a phone line at home, too.

The landline’s decline was precipitous once it got underway. In Oregon, the steepest declines were a decade ago, when the number of homes with their own phone lines dropped by more than 11% in 2014.

Oregon had fewer than 500,000 landline phones in 2022, the federal numbers show. That’s a mix of old-fashioned copper phone lines internet-based phones that act, for the most part, just like regular landlines.

Oregon had 4.5 million working cell phones in 2022, according to the most recent federal numbers. That works out to nearly one cell phone for every person in the state.

So who are those people who can’t quit their landlines?

They may be people who don’t want to give up a phone number they’ve had for decades — porting a phone number from a landline to a cell phone is often possible, but it can be a big chore.

Or they may be people who still see some advantage in landline phones. Many landlines still use the old telephone network that is immune to many internet outages, and those phones frequently continue working even when the power is out. And unlike cell phones and internet-based phones, these landlines are subject to state regulations that govern service quality.

Oregon doesn’t have data on landline phone customers, but the federal government collects national information on the characteristics of people with landline phones through an annual survey by the National Center for Health Statistics.

Only about 1 in 7 renters have landline phones, less than half the rate of those who own their own homes.

People in their late 20s and early 30s are the least likely to live in homes with landline phones, according to the survey. But a slight majority of people over 65 still have them.

Perhaps surprisingly, there are great regional differences. About a third of those living in the western U.S. have landline phones. The numbers are similar in the Midwest and South. But in the Northeast, nearly half of homes still have landlines.