A nationwide poll of over 2,000 Americans has found that 79 per cent now access the internet, up from barely 50 per cent in 2000.
Nearly a third of respondents access the internet away from their home or work connection, typically in cafés or using a friend's connection.
US citizens spend an average of 11 hours a week online, up from nine hours in 2006 and eight hours in 2005.
"As internet penetration continues to grow, the demographic profile of users continues to look more like that of the nation as a whole," said Harris Interactive, which carried out the telephone survey.
"It is still true that more young than older people, and more affluent than low-income people, are online, but nine per cent of those online are now age 65 or over, compared with 16 per cent of all adults who are 65 or over.
"Some 39 per cent of those online (compared to 47 per cent of all adults) did not [spend] at least some time at college, and 13 per cent have incomes of less than $25,000 (compared to 17 per cent of all adults)."
Overall the poll found that 97 per cent of computer owners accessed the internet on a regular basis and over four out of five people now own a PC.
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