Sales reached a seasonally adjusted annual rate of 414,000, down from the revised November rate of 445,000.
From a year earlier, sales rose 4.5 percent -- in December 2012, the seasonally adjusted annual rate of sales posted was 396,000.
The median sales price of a new home was $270,200 in December, down from November's $270,900.
The department said it would take five months for the inventory of 171,000 new homes on the market to sell at the current rate of sales.
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