The point is that everybody have its own coefficients in such formulas. Even if you are not counting production they are at least different for different chapters. Awhile ago we were using numbers derived from max culture you can get from regular (not event) buildings and population from regular residences. But now such equations looks useless as we have so many event buildings that no one sane would use regular culture and residences if he is not a newbie. + we have many culture buildings that are placed in our cities due to things they produce and not for the culture they give, which make culture part of non-producing event buildings worthless.