My 18 Barred Rock hens finally started laying and they had worked up to an average of 11 eggs a day. Now I am only getting 4 to 6 a day. No eggs are in the run that I have found. Shouldn't they be producing at least an egg per day? They all look healthy. I've never had this many hens at one time....when I had 4 hens we had 3 eggs a day most days.