New research conducted by Millward Brown IntelliQuest for the Online Publishers Association (OPA) indicates that nearly three in 10 at-work Internet users say the Internet is the only medium they consume during the day; and tenured users spend more time online during the day than new users.

Probing deeper into the online activities of working people, this new study provides insights into the ways that Internet usage levels, and 13 distinct online activities, vary by demographic group and time of day. In addition, the study provides further proof that online tenure (the number of years a user has been online) is a key determinant of usage levels and activity.

"This research broadens our understanding of the at-work audience and the subtle differences in how key demographic groups use online media throughout the day," says Michael Zimbalist, executive director of the Online Publishers Association. "As we learn more about the ways consumers have integrated the Web into their daily lives, it helps clarify the importance of this medium for advertisers seeking to reach some of their most elusive targets."

Specifically, the study found that Internet usage by day-part varies by demographics. For example, usage among top-level professionals exceeds all other at-work users during most day-parts by anywhere between five and 13 percentage points, with the greatest percentage (81%) found online in the morning before lunch (Daytime I). In addition, affluent users with annual incomes of $75k and above are more prevalent online throughout the day until evening, when average income levels of online users decline.

Generally speaking, a greater percentage of men are online than women during most weekday day-parts. While the highest percentage of both men (77%) and women (68%) can be found online during the morning before lunch (Daytime I), the greatest gender difference occurs in the Early Morning (6am to 8am), when 52% of men are online vs. only 39% of women.

For 13 surveyed online activities ranging from checking the weather to planning meals, daytime usage predominates, with the exception of shopping and multimedia downloads (a proxy in the study for online entertainment), which peak both during the daytime and also in the Prime Time TV viewing hours at night.

Online activity levels and patterns also vary by demographic group. For example, top-level professionals use the Internet in the morning to keep up with the news and to prepare for meetings, whereas shopping is dominant among this group at night. Affluent workers display similar patterns, with a slightly larger share of them engaging in online shopping activity during the lunch hour.

Other key findings from the study include:

• Working women avidly check the weather during the day and use the Internet to shop in the evenings, if they use it at all
• Working mothers focus on both weather and local information during the day; they are less likely to be online in the evenings than women overall
• Younger workers show greater interest in world or local news than in business news during the day, and are somewhat less likely to be shopping than the norm
• Older workers are more apt to check stocks after the market closes than during trading hours and to seek out entertainment in the Early Morning, rather than the evenings.

For every surveyed online activity, the more tenured users (those who have been online for 7+ years) displayed higher usage levels than the least tenured users (those online four years or less). This indicates that the more familiar users become with online media, the more ways they find to integrate it into their lives.

Seventy-four percent of at-work users say the Internet has improved their productivity at work. Fifty-six percent also indicated that they use the Internet at home for business purposes.

A detailed summary of findings from this study is available at the Online Publishers Association Web site at www.online-publishers.org.