To be technically correct - the best kind of correct - the show has only been cancelled twice. In fact, to be even _more_ technically correct, it hasn't actually been cancelled, just not renewed.

People tend to confuse the times after the films where there were no new episodes to show and none in production with a cancellation, because the films themselves did not bring the show back to television. That's like saying Arrested Development is cancelled after the film is released, because no new film or television episodes has been ordered.