Почему новый год является важным праздником?

Why beginning of a new year has such special symbolism? And why its celebration is so widely spread across the world, or at least where there are calendars? Behavior is, of course, due to something internal in the human mind, something deeply meaningful and important, given how much energy and resources we put into the party, how many are putting effort to make this moment special, taking a lot of restrictions. For what? It may be that the symbolism we attach to this issue relates to one of the most powerful motivations - the desire of humanity to survive.