Actually it has been calculated and that is why SETI is listening...
Even the most pessimistic estimates have earth-like planets in the hundreds of millions just in this galaxy. Statistically, half the civilizations would be older than humans, most much older. It isn't much of a leap to think the same tech that would produce faster than light travel would also bring faster than light communications. We just may be deaf... ;)
I would say even the most pessimistic estimates are optimistic.