Economic activity in Texas keeps getting worse. The general business activity index out Monday from the Dallas Federal Reserve for January was -34.6, a six-year low, and much worse than economists had estimated. The forecast for the index was -14, following the prior reading of -21.6 (revised from -20.1) that was also worse than expected. An index reading below zero indicates contraction. The index was sub-zero for all of 2015, as low oil prices.....