I enjoy a healthy margin of error +- 100.
Then take in tons of variables: summer=less screen time; chick days at TSC; weather patterns and so on and on.
Bottom line- I am much better at chicken math; everything else is my dumb luck🫣
30 cornish cross. I also have a broody sitting on Bielefelder/Lemon Cuckoo Niederrhiener eggs. Told hubs I needed to somehow check if the eggs were fertile — It’s better to let him think this is the only way to know—shhh. chicken math