65% of adult Internet users in the United States participate in social networks such as Facebook, Google+, Twitter or LinkedIn, up from 61% a year ago, according to a new report from the Pew Research Center, a not-for-profit research group that studies consumer behavior and the Internet.

Moreover, for the first time, half of all U.S. adults—not just those who say they are online—say they have interacted on social networks. That’s a huge increase from six years ago, when 5% of U.S. adult said the same.

Pew based its findings on a survey of 2,277 adults conducted in April and May.

The growth comes as social networks continue to transform consumers’ online experiences. Consumers can browse a retailer’s catalog, receive customer service and complete purchases on social networks.

Those innovations have helped make engaging on social networks the third most popular daily online activity for consumers, after using e-mail and search engines. On a typical day 61% of consumers say they use e-mail, 59% use a search engine and 43% of online adults use a social network—up from 38% a year ago.

Perhaps not surprisingly, social networks are most popular among younger consumers—83% of online adults ages 18 to 29 use social networks and 69% do so on an average day.

Even so, that doesn’t mean other age groups ignore social networks. 70% of adults ages 30 to 49 use social networks. That dips to 51% of those 50 to 64 and 33% of those 65 and older. But the 65 and older age group has the highest rate of growth over the past two year for social network use, increasing from 13% in 2009.