Despite falling U.S. auto sales, XM Satellite Radio delivered the highest number of vehicle based subscriptions in satellite radio history, said CEO Nate Davis during yesterday's earnings call.

"Even with the relative softness in the US auto-market, XM delivered the largest number of OEM growth additions in the history of satellite radio," Davis said.

XM had over 800,000 gross OEM additions and roughly a million factory installed XM radios manufactured and delivered to dealers in the quarter, Davis told investors. "That is a 48% year-over-year quarterly increase."

XM ended the quarter 355,000 net subscriber additions from the OEM channel, while Sirius brought in over 321,000 net subscribers from the automotive channel.

Still, XM had a net loss of 51,000 subscribers from the Retail channel, while Sirius squeaked out just over an additional 2,500 subscribers from Retail

Davis explained that while the company had successfully increased direct retail sales to their website and call centers, those increases did not offset "the continuing decline in overall retail sales through the big box retailers."

"However, offsetting this retail weakness... is a continued acceleration of our OEM growth," said the CEO. "XM 2008 installations could well exceed 4 million units close to the long range estimate we provided a number of year's ago."

[Transcript via SeekingAlpha]

I don't think anyone thought we would still be doing this comparison since the merger was announced, I sure didn't, but here we are again. The above chart shows the total cumulative subscribers comparing Sirius and XM.

Total Satellite Radio Subscribers:

• Sirius: 8,644,319
  
• XM: 9,330,000
  

But while the total subscriber numbers are interesting, I think it's the net and gross additions that are most significant.


Above is a chart shows the quarterly net subscriber additions dating back two years. Look at Q1 of this year: Sirius and XM are nearly equal in quarterly net additions. This is a significant shift from prior quarters where Sirius truly dominated.

Quarterly Net Additions:

• Sirius: 322,354
  
• XM: 303,000
  

So let's take a look at gross subscriber additions:
This chart shows a different picture of XM once again dominating gross subscriber additions - albeit, just barely.

Quarterly Gross Additions:

• Sirius: 1,003,422
  
• XM: 1,034,000
  

To their credit, XM did a great job in gaining gross subscribers from the same period last year - the question is whether this trend will continue for future quarters. But that's a question (at least for these Sirius vs. XM comparisons) that may not matter if the FCC actually makes a decision.