I had my hair cut by a woman who lives on a farm today (no jokes about shearing etc - thank you - FYI, she cut my hair in the hairdressers where she works, not in a barn, a yard or a field :)). She advised that:
1. Her mother has 12,000 free range chickens on the farm. Think that's a lot? Her aunt has 32,000.
2. When they are delivered to the farm, the chickens come 12 to a crate.
3. It takes 3 or 4 weeks before the chickens start to lay eggs - they are a bit young and need time to settle. They keep the chickens for 13 months or so, then they are sent for slaughter and a new batch brought in.*
4. When in full swing, as it were, the chickens lay 11,000 eggs a day.
5. Blue eggs have to be separated from brown ones. By hand. Every day. People pay more for blue eggs.
Bonus fact: the chickens have access to "pop holes" by which they can go outside the shed / building in which they are kept. It took a while but I eventually worked out that when she said "popples" she was, in fact, saying pop holes.
The chicken, below, is not on the aforementioned farm. In fact, it lives in West London (or at least it did - not sure if it is still alive now).
*The "natural" lifespan of a chicken is between 5 and 8 years.