I voted 70-80% and this holds true for both the group I am in now, as well as the one I played in for the last five years. The number is higher than I would like. I think age (with less time to actually play) and the current rules set are largely to blame. Actually more of the blame (if you can call it that) falls with the rules (D&D3.5), as the last group didn't see nearly as much combat in Legend of the Five Rings, Serenity, and other games as in D&D.
Chad