Nielsen has published its Top US Web Trends for July 2011. It is the first set of figures to use a new metric which adds online access via phones and tablets and includes site-side data.

The main value in publishing monthly statistics is so that interested parties can discern trends. Web developers as well as advertisers want to know about changes in audience behavior and so broadening the basis in this way is important given that the increasing number of mobile users are relying more heavily on these devices for online access. The one disadvantage of making this change is that this set of figures can't be compared with previous periods.

So first let's take a look at the past landscape based on home and work internet access. Putting together figures from earlier reports show that Google has remained at the top rank in terms of audience since 2008 and eight sites have been consistently in the top 10 even though they have sometimes swapped rank:

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The one major change in the above chart is that Facebook came in at number 3 in 2010, rising to number 2 by 2011, and its users spend much more time there than on any other site as shown below:

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The 2011 figure in the above charts is from May. This is because the new "Total Internet Audience" metric came into force in July. According to Nielsen the its advantage of using is that it:

should provide a more holistic perspective on how Americans use the internet.

The new "hybrid measurement" includes visits to websites from all sources, including mobile phones, tablets, game consoles, etc in addition to the Home/Work PCs and laptop computers already being tracked and uses site-side data using tags as well as usage data from an online panel.

Previously Nielsen's figures reported the month-on-month percentage change in overall number of sessions/visits per person, domains visited, web page views. Because of the introduction of the new system there is a step-change and so July's table does not include this data.

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The bottom line of the table for July 2001 is that 213 million Americans were active online and this compares with 200 million US consumers who went online from home and work PCs in May.

Looking at the proportion of the people who actually went online compared to all of those who had the potential to do so, using the hybrid metric the proportion is 77%, compared to 81% on the previous basis. This seems reasonable given that some users of mobile phones will use them only for the "primary" purpose of phone calls.

Interestingly, while the new metric records an increase in the number of sessions/visits per person (11%) and domains visited per person (14%) there is almost no change in the number of web page views per person (<1%), although the duration of a web page view increased from 58 seconds to 1 minute 6 seconds (12%). The new metric records Online Time per person for the first time and at over 27hrs per month this suggests an average of almost an hour per day per person is spent online.

So what difference does the new metric make to the Top 10 Web Brands?

The quick answer is hardly any. The very same sites are ranked 1 to 9 as in May 2011. Amazon, however, enters the list for the first time at Rank number 10, a position that was occupied by Ask Search in May 2011, by Fox Interactive Media in 2010 and by eBay in 2010.

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Making a deeper comparison between this table and the corresponding one for  May 2011 to discover more subtle changes from introducing the hybrid metric shows that while most sites see around a 10% increase there are exceptions. The outliers are YouTube which sees over 13% increase and AOL which jumps by  almost 18%. At the other end of the scale Wikipedia's audience only increases by less than 4%.

Looking at time spent online the use of the hybrid measure shows a decrease in the time per user spent on Facebook (-20%) however a note to the table shown below warns that:

Due to a change in the type of call used behind Facebook’s AJAX interface, Nielsen NetView data for Facebook duration will be under-reported for June and July. 

Decreased average duration was also in evidence for AOL (-12%) and Apple (-6%). On the other hand MSN/WindowsLive/Bing showed the greatest increase (19%) followed by YouTube (17%) and Wikipedia (14%).

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So although from July there is a step-change in Nielsen's figures going forward we can expect to be able to discern more comprehensive trends for the total US internet audience.

More information:

Nielsen

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