Study: 1 in 5 adults doesn't use the Internet

(CNN) - Here's some research that may shock you. One in five adults doesn't use the Internet.

The Pew Internet Project found half of those who don't surf the web say they don't think it is relevant to them or it is a waste of time.

Senior citizens and people without a high school education were among the least likely adults to have Internet access.

Nearly 40 percent of respondents with an annual household income under $30,000 also don't go online.

Most Americans who don't currently go online have never gone online before, and no one else in their home uses the Internet either.