WIN10 usage continues to grow, especially as it comes preloaded on new computers.  However corporate enterprise users are more locked into legacy devices, applications, and desktop management software continue to use WIN7 more extensively. 

http://www.zdnet.com/article/the-biggest-barrier-to-windows-10-success-is-still-windows-7/

Windows 10 has made some decent inroads thus far: it now accounts for somewhere around a quarter of PCs accessing the internet as measured by NetMarketShare. All data like this needs to be looked at in terms of trends rather than details, of course, but in December 2016 – the most current data available, Windows 7 stood at 48 percent, Windows 10 had 24 percent, Windows 8.1 held seven percent, Windows XP nine percent, and Windows 8 had just two percent.

In Windows 7, Microsoft built a good product that companies like. It’s now tried and tested, works with their existing infrastructure and their users are confident using it. And they worry about how big a leap it is to Windows 10, though more will no doubt consider the upgrade as Windows 7 heads towards the end of its lifecycle (Microsoft’s extended support, which included security updates, ends in January 2020).