I lived near two egg factories when i was a kid and they had a local sale room. I had to buy eggs once for my grandma for a big baking project . 50% of the flat of eggs had two yolks
How big was it? I just ate my huge one. 2.75" long. Also was just a huge double yolker. I get about 1/10 that are double yolks. But the one I post on here was much larger.
We don't know which of our 8 hens is laying it but we get one gigantic egg about 5-6 days a week....Most of them are double yolks but some are triples!