WASHINGTON (MarketWatch) — The Federal Open Market Committee, under the new leadership of Fed chairman Ben Bernanke, increased its target for overnight interest rates by a quarter percentage point to 4.75% Tuesday. This is the 15th straight meeting with a quarter-point rate hike. The increase in the federal funds rate was expected by traders and economists on Wall Street. Rates are at their highest level in five years. The vote was unanimous. The FOMC kept its Jan. 31 language that “some further policy firming may be needed.”