It makes sense that, as more households opt for wireless connections, landlines will be cut. A new study by the Centers for Disease Control confirms that.

Preliminary results from the January–June 2008 National Health Interview Survey indicate the number of American homes with only wireless telephones continues to grow. More than one out of every six American homes had only wireless telephones during the first half of 2008. The 2008 figure is an increase of 1.7 percent since the second half of 2007, when one out of every eight homes was completely landline-free. It is about 10 percent higher than the same figure for the first six months of 2005, when only one out of every 15 adults lived in wireless-only households.

In addition, more than one out of every eight American homes last year received all or almost all calls on wireless telephones despite having a landline telephone in the home.

The study revealed variations depending on different demographic groups. For example, nearly two-thirds of all adults living only with unrelated adult roommates were in households with only wireless telephones. This is the highest prevalence rate among the population subgroups examined.

The trend also appeared strongest in younger demographics, with more than one in three adults aged 25–29 years living in households with only wireless telephones. The percentage of adults aged 18-24 years living in a wireless-only household was almost the same, at approximately 31 percent.

Among other things, the study reveals that a migration to a wireless-only environment is stronger in metropolitan, well-to-do households. Adults living in metropolitan areas were more likely to be living in wireless-mostly households than were adults living in more rural areas, by a difference of 15 to 12 percent, and adults living in poverty or near poverty were less likely than higher income adults to be living in wireless-mostly households by a difference of approximately 10 to 17 percent.