U.S. Fed chairwoman Yellen moves cautiously to raise rates in December 2015. The Fed raises the benchmark federal funds rate-its overnight lending rate- from near zero to between 0.25% and 0.5%. Yellen emphasized her cautious approach by saying "we have very low rates and we have made a very small move." This follows seven years of near zero rates after the QE program for monetary easing under Ben Bernanke, the previous chairman, following the 2008 financial crisis. The Fed plans to raise rates gradually and slowly over 3 years. With oil prices falling below $35 the prospect that inflation may fall well below the 2% target could put off further plans to raise rates. Yellen said the Fed would "monitor inflation very carefully," and if it remained at unexpectedly low levels the Fed would reconsider its outlook and respond with "appropriate policy."