For interest:
Time until you pass someone on Golden Club:
|(Their golden club count - Your golden club count)| = X
(Your Golds - Their Golds) = Y
Y(time)=X
Divide by Y on both sides == Time=X/Y
Time comes out on days until you pass someone, remember || indicates take the absolute value, aka if its negative just remove the negative sign and make it positive. If Y comes out negative, (You have less golds than them) obviously you won't pass them until you fix that problem.
Simpler (The difference between your two GC counts) Divided by (The number of golds you have *more* than they have* (Your Golds - Their Golds)) = Days until you pass them, if it comes out as a decimal (almost always will), Round up. For years divide by 365.25.