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MEXICO CITY, Jan 8 (Reuters) - Mexico's annual inflation rate cooled in December but is still above the central bank's 4 percent ceiling, amid a deep slump in the peso that threatens to fan consumer prices higher.
Inflation in the 12 months through December eased to 4.08 percent, national statistics office data showed on Thursday, just below the 4.11 percent expected in a Reuters poll and down from 4.17 percent in November.
Mexico's annual inflation rate has begun to ease since hitting a nine-month high in October, and the central bank has said it expects inflation to approach its 3 percent target by around the middle of this year.
Mexico's central bank left rates on hold at a record low of 3 percent in December, but said a slump in the peso could add to inflation pressures.
Consumer prices rose 0.49 percent in December from November, compared to expectations for a 0.5 percent rise. Core inflation, which strips out some volatile food and energy costs, was up 0.23 percent, below the 0.28 percent expected in the Reuters poll.
Mexico's peso has tumbled more than 13 percent since the end of June, dragged down by plunging oil prices. The central bank restarted a dollar auction program last month to help cushion the peso's slide.
(Reporting by Alexandra Alper; Editing by Bernadette Baum)