https://www.theverge.com/2019/1/2/18164916/microsoft-windows-10-market-share-passes-windows-7-statistics

Microsoft finished 2018 as the world’s most valuable company, but it also passed an important milestone for Windows. The latest Windows 10 operating system is now the most popular desktop OS in the world, finally beating Windows 7’s market share according to Net Applications. Windows 10 held 39.22 percent of desktop OS market share in December 2018, compared to 36.9 percent for Windows 7. It’s a statistic that’s taken Microsoft three and a half years to achieve, and it demonstrates just how popular Windows 7 has been since its release nearly 10 years ago.

Microsoft had been planning to get Windows 10 running on a billion devices within three years of its release, but the company soon extended that timeline after it was clear that Windows Phone wouldn’t help it achieve this aim. Windows 10 is now running on more than 700 million devices, including PCs, tablets, phones, and even Xbox One consoles. Windows 7 has held on strong in recent years, despite Microsoft’s big push to get PC users to upgrade for free and even a “PC does what?” marketing campaign designed to target consumers who have four- or five year-old computers.