U.S. industrial output fell in February, according to new figures released Monday that showed output down for the fourth straight month and the factory operating rate dropping to the lowest level in the more than 50 years of record keeping. The Federal Reserve said that industrial output fell 1.4 percent last month, slightly worse than the 1.2 percent decline that economists had expected. The figures included a 0.7 percent fall in manufacturing output, which pushed the operating rate for U.S. factories down to 67.4 percent of capacity last month. That figure is the lowest on records that started in 1948. The decline came despite a rise in production at auto plants and auto parts manufacturers of 10.2 percent. Mining industry output was down by 0.4 percent and utility plant production fell 7.7 percent as the result of warm February weather that cut demand for oil and natural gas. The overall operating rate for manufacturing, mining and utilities fell to 70.9 percent of capacity in February, matching a record low set in December 1982 when the United States was emerging from the 1981-82 recession.