XM Satellite Radio, one of the two nationwide subscription radio services offered as factory options by many major US vehicle manufacturers, has exceeded most Wall Street analyst expectations for first quarter subscriber growth.

XM had more than 76,000 subscribers signed up by 31 March, more than doubling its total in the first quarter.

"XM added over 48,000 subscribers in the first quarter, exceeding its target by 15 percent, outpacing most Wall Street analyst expectations," said XM president and CEO Hugh Panero.

XM remains on track to end the year with 350,000 subscribers, Panero added. He said that the majority of XM subscriber growth has come from consumer retail distribution, however he also expects significant growth from the automotive sector in the second half of the year, when XM will become available in a variety of new car models.

The company has already made major inroads into the automotive sector. From this autumn, General Motors will offer XM on 23 Buick, Chevrolet, GMC, Oldsmobile and Pontiac models. GM already offers XM in Cadillac Devilles and Sevilles.

Some Isuzu dealers will also offer XM radios in Axiom and Rodeo models from this month. Isuzu has also designed and developed a mounting kit that allows its older models to be easily retrofitted.

Nissan will offer satellite radio systems in some 2003 vehicles from later this year and Volkswagen of America, which also includes Audi, has also signed distribution agreements.

Satellite radio, billed as the most major technological change since the introduction of FM almost 40 years ago, offers US consumers up to 100 coast-to-coast digital channels. XM's offering includes 71 music channels, of which over 30 are commercial-free, and 29 channels of sports, talk, children's and entertainment.

XM also offers similar 24-hour news sources to home cable and DIRECTV packages.

A rival satellite radio company called Sirus also offers similar services that compete directly with XM's.