PLENTY O' NOTHIN' (profanity alert):

Finance takes up fully 8 percent of our economy, up from less than 3 percent in 1950. But is our finance industry giving us anything now that it wasn't back then? [...]

All that trading, and the infrastructure to support it, occupy a vast number of Americans. But we have no idea how it creates value. Some forms of financial activity, such as high-frequency foreign exchange trading, are almost certainly useless. If people get paid money to do these things, it almost certainly must be because they either use the market to trick people out of their money, or because the government somehow subsidizes them. Our top financial economists are stumped. When I once asked a hedge fund trader how much value his job created for the world, and he cheerfully replied, "Oh, none. Zero. But they pay me a lot of money to do it!" [...]

Even as productivity has climbed strongly in most American industries, it has fallen in health care. More and more people are being hired by the industry, but the average amount they produce is going down and down. So whether you measure the value of our health-care industry in terms of how healthy we are or how much people are willing to pay, the picture is not bright. [...]

Finally, we have the education sector, which at 5.7 percent of GDP is also a big deal. Even as college tuition, already sky-high, continues to drift upward, many economists question whether college is worth what we pay for it. Does college really train students with the skills and life experiences they need to be productive?

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