Landline use continued to slide in the U.S. over the first half of the year with 35.8% of homes carrying only a wireless phone subscription, according to a report from the Center for Disease Control and Prevention, which says it tracks the trend in order to conduct more accurate surveys. The CDC also found an additional 15.9% own a landline connection but rarely, if ever, use it. Among those ages 25 to 29, 60% resided in homes without a landline.