Euro zone consumer prices fell by more than expected in December because of much cheaper energy, a first estimate by the European statistic office showed in data that is likely to trigger the European Central Bank’s government bond buying program. Eurostat said inflation in the 18 countries using the euro in December was -0.2 percent year-on-year, down from 0.3 percent year-on-year in November. The last time euro zone inflation was negative was in October 2009, when it was -0.1 percent. Economists polled by Reuters had expected a -0.1 percent year-on-year fall in prices. The ECB wants to keep inflation below but close to 2 percent over the medium term. Eurostat said that core inflation, which excludes the volatile energy and unprocessed food prices, was stable at 0.7 percent year-on-year in December — the same level as in November and October. But energy prices plunged 6.3 percent […]