From an Experian Hitwise Blog Post by James Murray:
In August 2011 there were 3.4 billion hours spent online by the UK Internet population, but if we distilled all usage into a single hour, this is how it would look.
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By far the biggest proportion of time spent online is on social media sites. In total there were 800 million hours spend on social sites in August, which translates to 14 minutes of our Internet Hour, almost a quarter of all time spent online. Amongst these, Facebook is still the clear market leader with half of all social networking visits and an average visit time of 22 minutes. Entertainment is the next biggest category, accounting for 9 minutes of our Internet Hour, with the majority of time spent on video on demand sites like BBC iPlayer and 4OD as well as movie and gaming websites.
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