In fact, Windows 7 users have upgraded -- and if past trends continue, will keep upgrading -- at a rate very near Computerworld's assumption, but Windows 8 and 8.1 users have lagged behind their upgrade-to-10 expectations. (The failure of Computerworld's model on 8/8.1 -- which concluded that two-thirds of all Windows 8 and 8.1 users would upgrade within a year's time to Windows 10 -- accounts for the gap between the low-end forecast of 308 million PCs running Windows 10 by July 31 and the 358 million predicted in 2015.)
Forecasting even further out with Net Applications' data, which by nature is imprecise and subject to the vagaries of the firm's methodology, has been iffy at best. But its crystal ball hints that Windows 10 will account for about one-fourth of all personal computer operating systems by the end of 2016, or at the 18-month mark. Previously, Computerworld bet that Windows 10 would reach the one-quarter yardstick within 13 months.
The data points to more than just prognostication abilities, but also -- assuming Microsoft's internal forecasting is similar -- why the company has turned up the upgrade heat on consumers and small businesses. Without the aggressive push, which was still a secret in early 2015, it's almost certain that Windows 10 would not be where it is today.
It's unknown whether Microsoft will extend the free upgrade offer, a tactic it could deploy to continue pressing adoption of the new OS. What has become clear is that the free upgrade has not dramatically changed the growth rate of Windows 10 from that of Windows 7, the most logical comparison. If Microsoft expected the offer to result in a substantial lead over Windows 7's trajectory, it's been disappointed.
The ball, of course, is in Redmond's court.
Computerworld's forecast puts Windows 10 on about 21% of all Windows PCs by the end of July, the operating system's one-year anniversary.
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