XM Satellite Radio Holding Inc. lost $146.6 million in the second quarter 2005, a $20 million improvement over losses of $166.1 million in the second quarter 2004, the company reported July 28.

Revenue in the second quarter 2005was $125 million, up 136 percent in the same period a year ago. XM attributed the revenue growth to a record 647,000 net subscriber additions in the second quarter 2005, which ended June 30. This represents a 55 percent increase over the 418,000 subscribers added in the second quarter of 2004. XM’s total subscriber count stood at 4.4 million at the end of the second quarter 2005, compared to 2.1 million subscribers at the end of the second quarter 2004.

Due to the strong growth in the first half 2005, XM increased its subscriber target for the end of the year from 5.5 million to 6 million.