Discussing how many things you get rejected from is probably bad PR, unless you're already so successful that it comes across as reassuring. Talk about it while you're still trying to make a name for yourself, however, it carries the risk of sounding whiney or even worse, naive, setting yourself up for averted eyes and hastily changed subjects. There may be, after all, a very good reason your work isn't making the cut, but everyone is too polite to tell you.
So, at the risk of both of those possibilities, here goes: I have applied for about nine art exhibitions in the last three months or so, and have received, roughly, seven rejections. (The remaining two I haven't heard from yet.) A few of these were easy to shrug of (the artistic equivalent of getting dumped by someone you weren't sure you wanted to date in the first place) though there were one or two that stung in particular, mostly because I'd assumed they were in were in the bag. In my head, I'd already pictured myself in the show, booking tickets to the location and posting triumphantly on Facebook. Yes, yes. Embarrassing now. Added to the pile are an influx of bait-and-switch commissions, which aren't rejections per se, but nonetheless deflating: "We'd love to have your work for [something really cool sounding]" most of which tend to fall by the wayside for whatever reason, once logistics, such as money, get in the way.