US at-home and at-work internet users - numbering some 221 million - logged an average of 60 sessions/visits each (up 3.5% from February) and spent an average of 19 hours and 42 minutes online at their PCs (up 3.2%), according to data (pdf) from Nielsen Online.

Nielsen's March data on US internet usage among all users:

• The number of web pages visited per person increased 2.8%, from 2,370 in February to 2,437 in March.
• An average of 105 domains were visited per person in March, a slight increase (1%) from the previous month.
• Internet users spent an average of 52 seconds on each web page viewed, one second less than in March.

Nielsen also issued a demographic breakdown of internet usage by the 164.6 million at-home and at-work internet users who were "actively online in March":

Actively online men…

• Spent a total of about 70 hours and 47 minutes at their PCs, on average.
• Logged 62 sessions/visits, on average.
• Constituted 48.7% of actively online visitors, viewing 2,622 web pages on average.

Actively online women…

• Spent less PC time than male counterparts (64 hours, 47 minutes, on average).
• Constituted the majority (51.3%) of active visitors, but viewed fewer pages on average (2,264).
• Logged 58 sessions/visits, on average.

Those in the 35-49 age group made up 26.3% of all actively online internet users, spending an average of 92 hours and 44 minutes at their PCs, about 7 minutes more than the second-largest age group (those 55+), who accounted for 22.7% of all actively online internet users.