Im going to say figure half. Your going to be left with 5-6 pounds.
Gotta figure in the weight of the bone ect. I always figure in 50% shrinkage. If anyone else wants to jump in and correct me please feel free to do so. Thats how I figure shrinkage here. Been very close IMHO.
I have been only getting 40% yield on my 10 lb butts. I'm not sure why, everyone else says they get closer to 50% - 60%. I inject them too. I do pick all of the fat out though.