But the fact that Windows 10's average week-over-week increases have been steadily shrinking, and more importantly, that they've dipped below those of Windows 7's for the last 6 days -- and in 8 of the last 12 -- signals that the biggest results from the free upgrade are behind Microsoft. Going forward, increases will likely be more in line with historical patterns.
The comparison between Windows 10 and Windows 7 is not apples-to-apples, maybe not even apples-to-oranges, since there are dissimilar variables, ranging from the time of year. Windows 7 at 40 days was into early December, PC buying prime time, while August is at the tail end of the second-best stretch, back-to-school, with few Windows 10-equipped devices yet on shelves. And there are vastly different personal computer dynamics in 2015 versus 2009.
Sans a free upgrade, however, Windows 10's increases would have likely been much, much smaller, far below Windows 7's, putting Microsoft in an impossible spot. But that counterfactual is impossible to prove.
One thing does seem clear: If Windows 10's usage share -- and data derived from other third-party sources -- doesn't improve at a faster pace, Microsoft could run through the 12 months of its free upgrade without enough to justify the effort, or make its professed goal of 1 billion Windows 10 devices by mid-2018.
Computerworld will check in on the progress of Windows 10's usage share gains at intermittent intervals.
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