Worryingly, not more than 5 years ago I couldn't find shirts to fit as hardly anyone was doing a 14.5" collar.
Now, years of motorcycle riding and steroids mean attempting to fit my neck into a 15" shirt is like watching a tortoise that has become too fat for its shell. I sort of splurge out of the top. The problem is that the rest of me is scrawny enough to not quite work in anything bigger. "Hello, is that the tailors? Good, I need you to deal with a scrawny steroid freak....".