In the summer and fall, my 12 hens averaged about 9 eggs a day. Now, I'm lucky to get 2 eggs a day out of them. Their coop never drops below 55 degrees Fahrenheit, and they have access to fresh, clean food and water daily. There aren't any predators around, and no other reason for stress. They all seem healthy, and I have a light on for them, but what could cause the decrease in egg production? Is this big of a decrease normal?