Don, I just emailed the Public Affairs office of the DOD asking them your question. Hopefully they will get back to me soon with an answer.
I tried searching online but couldn't find anything where the totals were broken down by branch of service.Not in numbers anyway. I did find a listing of percentages with the Army at around 71% and the Corps at around 24% for both Iraq and Afghanistan.
Leatherneck or the Marine Corps Gazzette might could provide you the answer too.
Semper Fidelis,
Chris
Later that night, while I was thinking about the day's somber events, Cpl. Richard A. Mason, an infantryman with Headquarters Platoon, who, in the short time I was with the company became a good friend, told me, "You're still here, don't forget that. Tell your kids, your grandkids, what Sgt. Peralta did for you and the other Marines today."
Quote from a story written by combat correspondent LCpl Travis J. Kaemmerer who,unfortunately,died in a car crash in Virginia after returning from Iraq.