Despite slight losses deriving from the catastrophic events in Japan, shares of Sirius XM (SIRI) jumped to a 52-week high on Monday after the broadcasting company said higher auto sales in the U.S. fueled an 85% improvement in first-quarter profit.

The New York-based provider of satellite radio services posted net income of $78.1 million, or a penny a share, compared with $41.6 million, or a penny a share, in the same quarter last year, matching the Street’s view.

Revenue for the three-month period was $724 million, up 9% from $664 million a year ago, short of average analyst estimates polled by Thomson Reuters of $736.3 million.

Strong auto sales, led by U.S. automakers such as General Motors (GM), Ford (F) and Chrysler, helped drive net subscriber addition to 373,064, an increase of 118% from the year-earlier period.

Total subscribers by March 31 landed just ahead of 20.5 million, partially offset by the March 11 devastating earthquake and tsunami in Japan, which has weighed on Japanese car sales as those manufacturers continue to face supply shortages. 

Sirius CEO Mel Karmazin said the first-quarter performance put the company on track to attain its fiscal goals for subscriber, revenue and adjusted earnings growth.

“Consumers are buying cars again and demand for our product is strong,” he said. “Were it not for the OEM supply chain uncertainty resulting from the tragedy in Japan, we would be in a position to raise our subscriber guidance today.”

In a statement, the company said it continues to expect fiscal 2011 revenues of $3 billion, in line with Wall Street estimates, with net new subscribers rising to 1.4 million.

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