I was asked the question earlier today ... how long have you been using Microsoft Excel? The answer for me was 24 years! Ouch! Am I that old!
Here's why ... we installed Microsoft Excel here at work because of its runtime windows version. We preferred the visual environment, and wanted to get off Lotus 1-2-3 and the backslash command. Thus, I was using Excel before we even had Windows 3.1. I also remember writing assembly code to install hard drives (5 meg).
Finally, here is the earliest version I can find of my research center web site which I worked upon (1997). Don't you just love the Wayback Machine, Mr. Sherman!