The Label Industry or Orville's Dillemma

I was making some popcorn and I noticed--as you'd expect, I guess--there was a food label on the box. I often wonder who comes up with the information on such labels, but for popcorn I had a different question. They say how many calories are in each serving. Now, does this assume every kernel pops, or do they take into account the ones that don't make it? This is not insignificant--sometimes I think I'm getting no better than 50% efficiency.