Depends upon the breed. I raise Buff Orpington and Barred Rock which are hardy birds for northern locals. (SW Wisconsin) Brown eggs, lay all year. The coop is inside of the barn and has two large south-facing windows so they get plenty of light.
Egg laying is dependent upon daylight hours. You can ‘fool’ some of the other breeds by keeping your coop lit 24/7.
My girls started laying in September. We have 11. We get 3-5 eggs a day, but you’re right - that will go down a bit in the long winter months.
And I know just how they feel! I am dragging until December 21st rolls around and we start getting more daylight every day until Spring! :)
Well we had a small operation of 150 chickens at most and it was an open coop with an enclosed nesting area. In the winter back then (around 50 years ago), the eggs dropped off by 2/3rds or more in the winter.