It's about your own code I suppose. I don't think there's any set rules. Here's the thing. Do you feel like you can honestly say you haven't drank for ___ days? Then those are the days you can feel good about. For me, if I took a sip, I couldn't honestly say I din't drink, because I did and for me that's a problem. If it's not a problem for you and you can live with having "sips" here and there and calling it a sober day, then so be it.
Just gotta be honest with yourself. I mean you can say whatever you want to us and make how every many days you want it to be. We're not the one's dealing with your drinking. Hope that makes sense.
We've all had the same question at one point or another but I think we all realize sober means sober and who wants to have a sober date they know in their heart isn't 100% true?