Zumiez said Wednesday that its sales improved in March, with a key revenue measure coming in much better than industry analysts had forecast. Its stock jumped 9.6 percent in extended trading on the news.

The Lynnwood-based action-sports clothing and equipment company said its total revenue for the five-week period that ended April 6 increased nearly 20 percent to $61 million, from $50.9 million last year.

Zumiez said its revenue from stores open at least a year increased 2.1 percent. That is considered a key measure of a retailer’s financial performance as it strips away the impact of recently opened or closed sites. It handily beat the 7.5 percent decline that analysts polled by FactSet had anticipated for the company.

The gain comes on top of a 14.1 percent increase in revenue from established stores for the month of March last year.

Zumiez said it benefited from higher prices and more items sold during the month. It saw improved sales in its juniors and hard goods departments, while its sales in its juniors, boys, men, accessories and footwear departments were softer.

The company operates 502 stores in North America and Europe under the Zumiez and Blue Tomato banners.

Its shares soared $2.40 to $27.30 in after-hours trading Wednesday. Its stock added 26 cents to close the regular trading day at $24.90.