Thank you for your question.
The Online Publishers Association (OPA) has released a White Paper
that identifies, examines and characterizes Internet day-parts. Among
the findings reported on in the paper is that audience share and
demographics of Internet content sites vary by time of day.
The paper concludes that five distinct day-parts exist on the
Internet: Early Morning (M-F, 6am-8am), Daytime (M-F, 8am-5pm),
Evening (M-F, 5pm-11pm), Late Night (M-F, 11pm-6am), and Weekends
(Sat-Sun, all day).
The study was based on U.S. Internet usage in September 2002 from
Hourly usage data for all 30 days in September was segmented by
gender/age, household income and usage location (home versus work), as
well as by site category.
The White Paper The Existence and Characteristics of Dayparts on the
Internet is available, free-of charge, at the OPA Web site.
You may download it directly from this URL
The Existence and Characteristics of Dayparts on the Internet
Daypart audience composition by age and gender page 8
Usage of top site categories by time of day page 10
Average minute audience by daypart page 5
Daypart Audience Composition by Household Income Level - page 7
Daypart Audience Composition by Location of Use - page 7
Source: Online Publishers Association
Internet Usage by time of day by age
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