I have 28 hens, eight are 16 months old, they are Olive Eggers, Rhode Island Reds, French Copper Marans, Buff Orphingtons, and Barred Rock. I also have 7 hens that were born in May, so new layers. The other hens are Splash Cochins, born in July, Lavender Orphingtons, born August 1, 2016. I am getting 3-4 eggs per day! I have them in two coops, feed them crumbles from Tractor Supply, they are warm, have water, plenty of food, aren't threatened by predators. I was getting 9-10 eggs until a month ago. The only thing I've changed is I've stopped letting them free range almost everyday due to them getting in a neighbors yard and digging in his grass. Any ideas?