China's central bank has raised interest rates for the third time in four months, as authorities step up efforts to tame inflation. The People's Bank of China said in a brief statement that it would raise the one-year deposit and lending rates by 0.25 percentage points each, taking the rates to 3% and 6.06% respectively. In October, policymakers raised rates for the first time in nearly three years as they try to restrain a flood of liquidity which has been fanning inflation and driving up property prices. Rates went up again on Christmas Day. China's consumer price index, or CPI, rose at an annual rate of 4.6% in December, down from 5.1% in November, which was the fastest rate in more than two years. The full-year CPI was up 3.3%, exceeding an official target of 3%. The government has raised its CPI target to 4% for 2011, as it is forced to acknowledge its limits in constraining prices. Fearful of inflation's historical potential to spark social unrest, authorities have already pulled on a variety of levers to try and rein in consumer prices and tame the property sector. These include the three interest rate hikes and a number of bank reserve requirement ratio increases.