Your 401k may be in freefall, but the recent stock market turmoil is great news for a wide swath of Wall Street. The dynamic is pretty simple: Volatility in financial markets spurs trading volume, which increases volatility. Rinse, repeat, and watch the bonus pool swell. To be sure, both trading activity and volatility have been rising recently as investors have grown jumpy about a range of factors, from Ebola, to plunging oil prices, to weakness in the European economy. Consider this morning's earnings report from Goldman Sachs. Revenue from institutional client services, the part of the bank that swaps big chunks of stocks and bonds for pension funds and the like, surged 32%, to $3.8 billion. Goldman doesn't make nearly as much money from trading as it used to. Still, it was a positive swing that analysts hadn't entirely expected.