Battlefield 3 Kill / Death Ratio Determination ? (K/D)

This may seem like a dumb question, but I am curious how DICE actually determines K/D.

Is your overall K/D determined by a absolute TOTAL of the player's kills / deaths?

Or is it based off of pulling an average from ALL of your rounds played and your K/D within it?

Hear me out: [maybe I am not as good in math as I think]

If I have a overall K/D of 10/5 (10 total kills and 5 total deaths in my current tour) and I then go 2/2 my next round, I go technically 1:1 or 1 K/D. That would then put me at 12 / 7 overall, being `2 (original K/D) + 1 (K/D after my second round) = 3 / 2 (total rounds played) = 1.5` average K/D overall (if they take averages of every round).

Otherwise, it would be just 12 / 7 = 1.714 complete overall K/D.

Maybe I am getting mixed up in my (possibly flawed) logic. Input? Ideas? Any DICE employees out there?

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I don't know how this actually works in that game, but the only sensible way of computing a kill/death ratio is to use the actual number of kills divided by the actual number of deaths. An average like you are describing could be messed up completely just by killing one person in a round and then hiding in the corner for the rest of the game (think of what a 1/0 would do to the average) – murgatroid99 Jan 23 '12 at 15:53