Nope I don't have that figure handy unfortunately. I do remember the SECDEF briefing it at a press conference at or was it Gen Pace???, at the PEntagon though.
Just from what my soldier and her group tried to figure, for calculations ease, about 150,000 are deployed in Iraq at any given time, many are on their 2nd or third rotation. A about 3 million military. The percentage is pretty low, just by that ball park guesstimate. Add in a factor for Afghanstan.