Pandora Shares Surge on Impressive User Numbers

The digital music company says it captured 8.6 percent of the U.S. radio market in December.

Shares of Pandora Media rocketed 14 percent Monday after the digital music service announced a new ad campaign and disclosed impressive listener hours for December.

The company said it had 76.2 million active listeners in December, up 13 percent compared to the same month a year earlier. Pandora said listening hours also grew 13 percent, to 1.58 billion in December.

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Pandora's share of the U.S. radio market was at 8.6 percent in December, up from 7.6 percent a year earlier, the company said Monday.

Shares of Pandora surged $3.90 to $31.49 on Monday. The stock also touched an all-time high of $32.45 prior to the close. At the close of trading Monday, Pandora sported a market capitalization of $6.1 billion.

The company also said Monday that 4 million users have activated their Pandora service in their vehicles and that the firm will begin to roll out an in-car advertising solution this month. On board as advertisers thus far are Ford, State Farm, Taco Bell and energy firm BP.

"Nearly half of all radio listening takes place in the car," said Pandora chief marketing officer Simon Fleming-Wood. "We knew early on that to redefine radio, we would need to seamlessly deliver Pandora through in-dash entertainment systems."