XM Satellite Radio Holdings Inc. reported a year-end subscriber tally Friday that fell short of its earlier forecasts, which already had been lowered twice previously.

XM, the larger of the nation’s two satellite radio broadcasters, said it ended 2006 with 7.63 million subscribers. That was up almost 1.7 million from a year ago but came short of its most recent prediction of 7.7 million to 7.9 million. A year ago, XM was forecasting 9 million subscribers at the end of 2006. It cut its forecast in May and again in July.

XM also said it turned a profit on an operating basis in the fourth quarter.

Earlier this week, rival Sirius Satellite Radio Inc. said it finished the year with more than 6 million subscribers, meeting a lowered estimate. Sirius also said it turned profitable on an operating basis.