The December Producer Price Index (PPI) came in cooler than expected, as equities rose in early trading, sold off, and then rebounded. The Dow Jones Industrial Average ($INDU), S&P 500 ($SPX), S&P 400 Mid-Cap Index ($MID), and S&P 600 Small-Cap Index ($SML) closed higher. The Nasdaq Composite ($COMPQ) and the Nasdaq 100 Index ($NDX) closed...