The issue: when your civ is not in a Golden Age, the happiness count is displayed along with the next total that will trigger a 15-turn Golden Age. When your civ is in a Golden Age, the happiness count (I think I read it referred to as a "bucket" before release) is not displayed, although the happiness level is. When you emerge from the Golden Age... the happiness count is exactly where you left it, however many turns before, no matter what your happiness level has been in the interim.
I'm posting this as a bug because, although I could find no documentation on the mechanic, it makes zero sense for this to be working as intended; not only is it exploitable (the count neither rises nor falls during a Golden Age) but it renders a lengthy Golden Age potentially more harm than good (exactly what happened to me in a game I just won). Golden Age time in every other circumstance is cumulative, and this bug breaks that mechanic.
I'm posting this as a bug because, although I could find no documentation on the mechanic, it makes zero sense for this to be working as intended; not only is it exploitable (the count neither rises nor falls during a Golden Age) but it renders a lengthy Golden Age potentially more harm than good (exactly what happened to me in a game I just won). Golden Age time in every other circumstance is cumulative, and this bug breaks that mechanic.