The ratings on Sirius Satellite Radio Inc. reflect the considerable challenges it faces in the early stage of launching its new, nationwide, satellite digital radio service. The company must still prove the technical viability of its system, its ability to meet targeted milestones, and its competence as an operator. In addition, significant uncertainty remains regarding consumer demand for pay radio and the cost of attracting users. Sirius will also need a large amount of additional funding before it reaches cash flow self-sufficiency. To date, the company has raised more than $1.8 billion. Sirius holds one of two FCC licenses to build a nationwide, satellite digital radio service. Satellite radio is designed to offer subscribers enhanced, fee-based services as an alternative