LOS ANGELES: YouTube's US traffic is set to pass that of Facebook within the next three years as the number of hours spent there annually by users will grow more than ten times as fast, new research has calculated.

A report from the University of Southern California's Marshall School of Business, How Much Media?, used data from Nielsen, comScore, analysts and company disclosures to estimate that users would spend a total of 15,141bn hours on YouTube by 2015 (from 7,217bn in 2012) compared to the 14,521bn spent on Facebook (from 13,110bn in 2012).

While Facebook will still be ahead in terms of the number of unique visitors, at 150m per year, down from a peak of 166m in 2011, the gap is expected to close from the current figure of 31m to 14m.

Overall, the study found that Americans receive a massive amount of media daily, while consuming only a small fraction. In 2008, this amounted to an average of 33 gigabytes per consumer per day, a figure which had almost doubled in four years to 63 gigabytes in 2012. Much of this was down to games, which accounted for over one third of media bytes consumed in the home.

In terms of time, Americans spent 11 hours per person per day receiving media in 2008, rising to 13.6 hours in 2012 and expected to hit 15.5 hours per person per day in 2015.

The number of hours of consumption grew at just over 5% a year between 2008 and 2013 thanks to a combination of increasing viewer hours, up from 11 hours per person day to over 14 hours, and population growth.

Traditional media continues to dominate daily media consumption, with TV and radio contributing 60% of the total hours, but the report said that mobile TV and internet video could cause "significant dislocations" in the future.

Mobile TV was essentially a niche product while internet video was growing fast. To date, however, internet video was "a complement rather than a substitute for conventional TV program delivery".

Data sourced from University of Southern California; additional content by Warc staff