Is there a calculation to figure out what the dressed weight will be versus the live weight, or is it so variable that there is no way to guess? I have a rooster who just started to crow so will soon need to be processed, since I can't keep roosters in the city. I weighed him and he only weighs 4# live (and that was with a full crop). He is a BO. I can keep him a little longer since his crows are not yet loud and its the time of year when our neighbors have their windows closed so I don't think he'll bother anyone, but his time is drawing near. I know he's not going to be a huge meal, but wanted to try to figure out just how small a meal he will be....