In a similar move to rival web measurement firm Nielsen//NetRatings, comScore has decided to make change to the way it measures web audiences.
comScore will now divide internet audiences into heavy, medium and light users, in an attempt to help advertisers better segment their audiences.
The 20% of the online audience that spends the most time online will be defined as heavy users, the next 30% as medium users and the remaining 50% as light users.
The reason for the change is the fact that a minority of users visit more websites and view more pages than the rest.
For example, comScore said heavy users spent an average 97 hours online during May, while light users spent just 3.6 hours.
Recently, measurement firms also abandoned the page impression metric as it doesn't necessarily give a true picture of a website's popularity.
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