What's going on here? I was impressed by the third quarter's 7.2% annualized GDP growth, but then I read that the corresponding non-farm productivity increase wads 8.1%! Whenever productivity growth exceeds output growth, there is a net job lost, in this case 41,000 non-farm jobs. Will we ever figure out what is causing this productivity boom? Last time I checked economists were stilling arguing about the productivity increases of the nineties, though I remember some paper showing that a disproportionate chunk of it was due to Wal-Mart. I can't content myself with a salute to the undeniable ingenuity of my fellow Americans; I'm too curious. Also, understanding past productivity growth can assist current productivity growth.