I read a long time ago that a good egg laying chicken in her prime will give you on average 2 eggs every 3 days. So 15 layers will give you ten eggs a day on average, and I've found that to be fairly true for us. We keep about 30 layers and we get maybe 18 to 20 eggs a day when they are in "laying mode."
I love the Aurucana breed. They make green and blue shelled eggs and really seem to perform well on less feed than the dual purpose breeds like Rhode Island Red or Buff Orpingtons.
