The U.S. market for digital satellite radio will increase at a compound annual growth rate of 35 percent, pushing up the installed base of receiving devices to 55 million units in 2010, from the current 12 million, according to a Jupiter Research study. Twenty-three percent of the online consumers Jupiter Research interviewed expressed interest in the service, but only a quarter of them presently have a satellite radio. XM leads the nascent market for nationwide pay radio, with more than double the number of subscribers at rival Sirius Satellite Radio.