It may be tough to believe given our connected audience but it's true: nearly one out of every three adults in the US don't have high speed Internet access at home. What's more, three percent of American adults still connect to the web using a dial-up connection - a figure that's held steady over the past two years - according to the latest survey from Pew Research Center's Internet & American Life Project.

The research firm further found that the number of adults that don't use the Internet has dropped by 50 percent over the past five years, from 30 percent to just 15 percent. It appears that much of this growth comes from smartphone usage and accessing the web at work.

As was the case in previous research, college graduates, adults under age 50 and adults living in households earning at least $50,000, as well as whites and adults living in urban or suburban areas represent those with the highest rates of home broadband adoption.

Kathryn Zickuhr, research associate for the Pew Research Center's Internet Project and lead author of the report said they've consistently found that age, education and household income are among the strongest factors associated with home broadband adoption. Many dial-up users cite cost and access as the main reasons they don't have broadband, she said, but for adults who don't use the Internet at all, a lack of interest is often the main issue.

Elsewhere, 46 percent of Americans polled said they have both a smartphone and broadband access at home. 24 percent reported having broadband but no smartphone while 10 percent had a smartphone without high-speed Internet access at home.