Understandably, this is not one of those instances where a generalized answer applies because profitability will depend on individual farmers and the facilities they own. What plays a part in how much profit a farmer can make?
There are LOTS of variables depending on your location and your individual property. Do you have pastures and housing for livestock? Do you have a water source? Do you have a food source? Do you have a source for a starter herd? Do you have a market? What sells best in your area? As always, it's best to start with contacting your local cooperative extension. Livestock that is profitable in my area, may not be profitable in your area.
Well, raising healthy chickens is not the only guarantee of a profitable egg business. First, you have to have a plan that identifies the target market and potential growth areas, be well versed with laws regarding egg selling in your area, and choose expert layer chickens.