CDC relies on landline phones for health surveys , conducted every year . The phone numbers are provided by the local telephone company and they have a database of all calls made to that number in their system. The new report is based on 2007 data , which found that Oklahoma had the highest percentage of cell phone -- only homes ( at 26 percent ) and Vermont has the lowest ( 5 percent ) . 26 percent of Oklahoma were cell phone-only homes ; Vermont had 5 percent .
CDC relies on landline phones for health surveys , conducted every year . The phone numbers are provided by the local telephone company and they have a database of all calls made to that number in their system. 26 percent of Oklahoma were cell phone-only homes ; Vermont had 5 percent .