Much has changed in the U.S. economy since Federal Reserve officials last issued their economic projections, in September. Oil prices have fallen by more than one-third, the dollar has climbed 5.3% against a broad basket of currencies and about 800,000 more Americans have found jobs. These developments present overlapping challenges as Fed Chairwoman Janet Yellen and her central-bank colleagues wrestle with shifting fundamentals at home and mounting jitters overseas. She will hold a news conference Wednesday, after the Fed’s two-day policy meeting, to discuss the central bank’s outlook and plans going into 2015. Falling oil prices are a boost to the U.S. consumer. But lower prices also are putting downward pressure on already low inflation, potentially moving the nation further away from the Fed’s objective of 2% annual increases in consumer prices. If Ms. Yellen and her colleagues put more weight on the looming inflation drop, they will […]