Shares in J.C. Penney Co. are tumbling in aftermarket trading after the department store chain posted disappointing results for its key holiday-shopping-season quarter.

The company reported a loss of $59 million, or 19 cents per share, in the three-month period that ended Jan. 31.

But excluding one-time items, it said it broke even for the quarter. Analysts had expected a profit of 12 cents for the period on that basis, according to FactSet.

Revenue rose 2.9 percent to $3.89 billion, edging analysts' estimate of $3.87 billion.

Sales in stores open at least a year rose 4.4 percent for all of 2014. The company expects that metric, a key one for retail, to rise 3 to 5 percent in 2015.

Penney's shares slid almost 10 percent in aftermarket trading.