Unexplained dough weight loss

Hello, friends.

  Happy fathers day to all the dads! Today I will be experimenting with a new Sicilian pizza pie. I have a quick question. On paper, I should have ended with a dough ball weighing 1,349 grams. I did not see very much bowl residue at all. However, the weighed dough just out of the mixer was just 1,317 grams. That is just over an ounce shy of what I was expecting. My question is twofold, is an ounce of dough loss normal/ acceptable? Not seeing what would account for the ounce of loss left in the bowl, what else would account for the weight loss? Could it be evaporation?

  Today, (Father's day) we have "The Pop-Pop" Sicilian pizza pie. The main changes from my last Sicilian pies follow.

1. The 70% hydration dough amount for the 16X16 pan is up from 21/2 pounds to nearly 3 pounds.

2. The par-bake method is what I call the modified Bellucci method.

A generous amount of Pecorino Romano cheese on the raw dough pre-par-bake.  4.5 oz. of full-strength sauce over the hard cheese, pre-par-bake.

 3. 3/4 cup of boiling water for a shot of steam at the par-bake start.

Everything is looking great! Nice and "beefy," hopefully airy too. Now the base can set up for a good few hours before the topped final bake.