Windows by the numbers: Windows 10 backtracks, Windows 7 remains resilient
Windows 10 in September faltered in its battle to replace Windows 7, losing its chance this month of putting the older operating system in second place.
According to California analytics vendor Net Applications, Windows 10 retreated by four-tenths of a percentage point in September, putting its user share at 37.4% of all personal computers and 42.8% of those running Windows. (The second number is always larger than the first because Windows never powers all personal computers; in September, Windows ran 87.6% of the world's systems. The remainder ran macOS, Linux or ChromeOS.)
September's decline was one of only five recorded in the 38 months since the mid-2015 launch of the newer OS. More common has been Windows 10 advancing its user share: its monthly average has been an eight-tenths of a percentage point increase. In all but one of the prior cases where Windows 10 lost user share, the slide was brief and gains immediately resumed.