This paper investigates the remarkable extremes of growth experiences within countries and the changes that occur across growth transitions. We find two main results. First, virtually all but the very richest countries experience both growth miracles and failures over substantial periods....

Great achievements in knowledge are produced by older innovators today than they were a century ago. Nobel Prize winners and great inventors have become especially unproductive at younger ages. Meanwhile, the early life cycle decline is not offset by increased productivity beyond middle age. The...