In 2015, Microsoft officials said they expected Windows 10 to be on 1 billion devices by late summer 2018. Today, on March 16, Microsoft execs said they reached that 1 billion “monthly active device” device target.

Microsoft’s former head of its operating systems group, Terry Myerson, announced the original 1 billion device goal for Windows 10 at Build 2015. Myerson and team said that 1 billion figure encompassed all kinds of devices that will be able to run the OS in some flavor, including desktops, PCs, laptops, tablets, Windows Phones, Xbox One gaming consoles, Surface Hub conferencing systems, HoloLens augmented reality goggles and various Internet of Things (IoT) devices. At that time officials also said they expected the majority of those 1 billion devices to be PCs and tablets.

A year later, Microsoft execs conceded they were unlikely to make that 1 billion by 2018 goal.

Between 2015 and 2016, as I wrote at that time “the bottom has fallen out of the Windows Phone market. In addition, Microsoft’s moves to try to get Windows 7 and 8 users to migrate to Windows 10 by offering them a “limited-time”  free upgrade — an offer which still works for many customers, by the way, using valid product keys — didn’t have much of an impact on the total, as relatively few users got a new version of Windows via a manual update. (Most get it via a volume licensing agreement or via a new PC preloaded with a particular new operating system.”

“Today we’re delighted to announce that over one billion people have chosen Windows 10 across 200 countries resulting in more than one billion active Windows 10 devices,” said Yusuf Mehdi, Corporate Vice president of Modern Life, Search and Devices, in a March 16 blog post.

Microsoft officials also said as of now the company has 17.8 million registered Windows Insider testers, though, according to my contacts, only a small fraction of this number actually regularly test Windows 10 feature update builds before they’re released. And Windows 10 currently runs on more than 80,000 different PC configurations and models, today’s blog post states.