By John S. McClenahen Led by a turnaround in petroleum prices, the U.S. Labor Department's Import Price Index increased 0.4% in January, the first time it had risen since May 2001. Prices for petroleum products increased 6% in January, following a three-month decline of 30.6%. Overall, import prices dropped 4.6% in the final three months of 2001 and 9% for the full year. "While the plunge in oil prices has ended, the bounce in January does not appear to be the start of a trend," reassures Maury Harris, chief U.S. economist at UBS Warburg LLC, New York. In January the department's Export Price Index fell 0.1%, its 11th decline in 12 months.