According to a new report issued by Forrester Research Inc., inhabitants of 20.1 million households will listen to satellite radio by the end of the decade. In its report, “The Future of Digital Audio,” the company notes that satellite radio reached 4.5 million subscribers by the end of 2004, a jump of more than 150 percent from the 2003 year-end subscriber totals. The report states that for satellite radio subscriber numbers to grow steadily beyond 2010, when it predicts that satellite’s prime market of higher- income, entertainment-oriented, technology-optimistic households becomes saturated, satellite radio providers should consider offering multi-tier subscriptions to reach the more than 85 percent of U.S. households that fall outside this wealthier, early-adopter segment.