How Cell Phones are changing the way we communicate.

The most recent survey by Centers for Disease Control and Prevention conducted from July to December 2008 in in-person interviews with members of 12,597 households, showed that because of the growing appeal of cell phones, at least 20% of households in the US used cell phones as the only form of communications in their residences. That was an increase of nearly 3 percentage points over the first half of the year, the largest six-month increase since the government started gathering such data in 2003.That ratio has changed starkly in recent years: In the first six months of 2003, just 3 percent of households were wireless only, while 43 percent stuck to landlines.

Further underscoring the public’s shrinking reliance on landline phones, 15 percent of households have both landlines and cells but take few or no calls on their landlines. Combined with wireless only homes, that means that 35 percent of households – more than one in three – are basically reachable only on cell phones.

The changes are important for pollsters and telemarketers, who for years have relied on reaching people on their landline telephones. Growing numbers of surveys now include calls to people on their cells, which is more expensive partly because federal laws forbid pollsters from using computers to place calls to wireless phones.

About one third of people age 18 to 24 and 4 in 10 ages 25 to 29 live in households with only cell phones, making them far likelier than older people to rely exclusively on cells.  Those likeliest to live in wireless-only households also include the poor, renters, Hispanics, Southerners, Midwesterners and those living with unrelated adults, such as roommates or unmarried couples. 60% of households have both landline and cell phones.