My regular Friday Night gaming group (I'm a player, not the DM) is all about the combat. Lately our gaming sessions last for about 5 hours, and except for a 30-minute prologue and a 30-minute epilogue, the whole thing is just one combat scene...or two combat scenes, separated by a short rest. Every now and then, rarely, we will have a trap or puzzle to figure out, but those are few and far between. So I voted for the 71-80% range.
In my other group (that I DM), it's quite different. There's about 2 or 3 combat scenes per gaming session, but the battles typically last only 20 or 30 minutes each unless something strange is going on (like a boss battle or a lair monster). Most of our gaming session is spent talking in-character, chatting around the campfire or haggling with merchants, or trying to decipher a clue. I'd say combat only accounts for about 31-40% of that gaming group...but we're currently on hiatus, so I couldn't vote for that one.