FRAMINGHAM 1 MARCH 2011 - Microsoft's Internet Explorer (IE) browser gained more market share last month than at any time in the last three years, but at least part of the boost came from an accounting change by Web metrics firm Net Applications.
Meanwhile, Microsoft argued that its share should be calculated only as a percentage of the browsers run on Windows.
According to Aliso Viejo, Calif.-based Net Applications, IE's usage share rose by nearly eight-tenths of a percentage point to finish February at 56.8%. It was first time IE climbed since July 2010, and was the largest one-month increase since Net Applications started tracking Microsoft's browser.
But Net Applications attributed part of the increase to a change in how it weights browser data.
Like most Web measurement firms, Net Applications has more data on some countries -- the U.S., for instance -- but relatively small samples from others, such as China. So to produce what it believes is a more accurate representation of browser usage, Net Applications weights its Chinese data proportionally higher because that country has an greater percentage of the world's Internet users than the U.S.
Starting with February's numbers, Net Applications used revised online population numbers provided by the U.S. Central Intelligence Agency (CIA) that showed a large increase in the global percentage of Chinese users, with a corresponding drop in the worldwide percentage of users from the U.S., the U.K, Canada, France, Germany and other developed countries.
"This shows that China is far more influential in browser usage than anyone realizes," said Vince Vizzaccaro, vice president of marketing for Net Applications.
Using the revised CIA Internet population data caused IE's share to jump because the vast bulk of that nation's users run Microsoft's browser, not a rival like Mozilla's Firefox or Google's Chrome.
According to Vizzaccaro, the new numbers "correct an increasing inaccuracy over time as population shifts occur and reflects reality more closely than unadjusted numbers."
The result? IE jumped, and Firefox fell.
Firefox's share of the global browser market dropped by a full point, it's largest change in nearly two years, to end February at 21.7%, a mark equivalent to its December 2008 share.
"If you look at Firefox, for example, it's very dominant in Europe," said Vizzaccaro. "But it loses global share since many of the countries in Western European now have a lower percentage of global internet users."
Google's Chrome and Apple's Safari still posted gains even with the new CIA data applied, although their increases were smaller than the average of the preceding three months.
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