not enough eggs and balding chickens

[thetinleys]

I have 20 chickens who are over a year but I am only getting 10 eggs a day. Dont most chickens lay one a day? I have a large coop, enough for more chickens, and have a good egg laying station that they all fit in. I give good water, laying pellets and oyster shells. Also most of them are missing the back end feathers right before the tail. We are always dusting for mites, cleaning coop and do not have any pecking issues that we know of. help...........................

 

[thetinleys]

I also forgot to mention that this is not a molting issue as far as low egg production. I have 10 barred rock, 1 blk wydonot, and the rest are RI reds. They have never really produced as good as they should. They have a large shed and a large fenced in pen, but they are outside of it most of the time. The pen is for at night and for weekends when I am not home.