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What: Shares of sports apparel retailer Zumiez (Nasdaq: ZUMZ) are scoring major gains, up as much as 26%, after the company reported third-quarter earnings yesterday.

So what: Third-quarter revenue jumped 13.3% to $154 million, while diluted earnings per share rose 12.5% to $0.45, topping the market's expectation of $0.42. Comparable store sales jumped 8.4% in November.

Now what: Fourth-quarter outlook also topped estimates, as the company expects comps to rise into the mid-range of the single digits, with sales of $174 million-$177 million. Zumiez expects earnings of $0.52-$0.54, compared to the estimate of $0.52. The retailer has opened all 45 stores it had planned for the year, including its first foray into Canada.

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