We have two versions of the entire Microsoft Office suite here at home that are way older than any of you are talking about - so you'll laugh, but here they are (both are Windows versions):
OFFICE 2003. A friend gave me a hacked install disc many years ago, and it has continued to install and work repeatedly even on the Win10 machines Kristi and Nathan have. (Mine's still a Win7.) She's a writer, she knows Word and Publisher 2003 inside and out, and has never wanted to move on from that version, the last one before Microsoft implemented the "ribbon" style of menus. It includes all the features she needs. Its Word files are ".doc" as opposed to ".docx" which I believe started with...
OFFICE 2007. When my then-employer was moving the company to OFFICE 2010 or whatever the next major implementation was, they had a deal with Microsoft that employees could purchase our own legitimate copies of 2007 from Microsoft for something like $15 or $20. I was used to that version and jumped at the offer. I still have the special install disc Microsoft sent, and I don't know if there was a limit on number of times I could install it, but it hasn't been any problem yet. I'm an Excel user, and have dabbled in Access, the powerful database program that isn't even available in the Apple world. So, even though most things I do are on a Mac now, I keep a Windows machine for the Microsoft suite and a couple of other Windows-only things, and I have no reason whatever to move on from there.