We develop a procedure to rank-order countries and commodities using dis-aggregated American imports data. We find strong evidence that both countries and commodities can be ranked, consistent with the product cycle' hypothesis. Countries habitually begin to export goods to the United States...

In this paper we examine how to account for growth when new inputs are being created. In particular, we obtain a decomposition of growth into that due to a higher quantity of existing inputs, and that due to a greater range of inputs. This decomposition is first obtained for a single firm, with...