How many use old browsers (e.g. =< Netscape 4 or IE 6) as their ONLY source of web content?

Hi, I'm engaged in a Retrochallenge project where I'm recoding my classic-computers.org.nz site to make it suitable for mobile platforms. I want to modernise the code as well, making it as close to HTML5 standard as I can The RetroChallenge blog site is here. http://www.classic-computers.org.nz/blog/2015-06-29-recoding-classic-comput… . In doing this, I will probably need to say goodbye to old browser compatibility. As in old I mean Netscape 4 or earlier, and other pre-2000 browsers (and possibly IE 6, as it's not very standard). The website does have a few articles and resources of interest to vintage computer hobbyists, which I wouldn't want to make inaccessible. The question is, how many guys like us, those who dabble with old tech, are likely to use ancient browsers as their ONLY source of web content. I suspect not many. Should I worry about it? Any comments welcome. On a related note, I'd be interested if anyone on the list CAN'T read this page properly: http://www.classic-computers.org.nz/blog/temp.html It's a new blog page template I've developed using HTML5 and is mobile friendly. If it doesn't show up properly I'll be interested to know what browser you're using. Please be kind about the HTML5 and CCS code. I don't do this for a job, and it's a big learning curve for me. P.S. Here are some interesting stats. For myself, I've been a Chrome user for a number of years now. http://www.w3schools.com/browsers/browsers_stats.asp Terry (Tez)