StatCounter pegged Windows 10 usage share -- of all the personal computers running a flavor of Windows -- at 33% for January; meanwhile, Net Applications' user share for the same month was around 28%.
It's unclear why the company has not updated the 400 million number for nearly half a year, when from the available evidence, the OS has gained users. Microsoft had told Wall Street that the number of Windows 10 "active users" -- those who had run the operating system at least once in the past 30 days -- would be one of the core metrics it would regularly tout.
"Going forward, we will track progress by regularly reporting the growth of Windows 10 monthly active devices," said CEO Satya Nadella during a July 2016 earnings call with financial analysts.
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