As smartphones have become a constant companion for most people in the United States, landline phones are rapidly losing their relevance. In 2004, more than 90 percent of households in the U.S. had an operational landline phone - now it’s little more than 40 percent. That’s according to data provided by the Centers of Disease Control and Prevention, which has been tracking phone ownership in the U.S. as a by-product of its biannual National Health Interview Survey since 2004.

If the trend continues at the current pace, and there’s little reason to believe it won’t, landline phones could soon become an endangered species, much like the VCR and other technological relics before it.