We have fifteen BOs. They will be fifteen months old tomorrow. We have been getting an average of about seven eggs per day for the past couple months. I finally put up a calendar this morning to track the number of eggs per day. So, three-or-four seems to be the average per bird per week. Of course, I live way up north in Wisconsin, and the temps have been a bit cool this summer, so your mileage may vary.
[EDIT] -- After hitting the submit button, I see you are in Duluth. I'm two hours east, and half-an-hour south.