My first flock 30 years ago were Khaki Campbells developed by a fellow named Holderread near Philomath Oregon. That fellow has since gone on to heirloom breeds. His stock produced about 360 eggs a year per hen, regularly. They got quite a few rewards. My flock at that time was 6 hens, once they started I rarely had a day go by without at least 5 eggs. These were ducks being used for limited retriever training and herding. Knowing now what I didn't then I would have been surprised that we had eggs at all.
My current Khakis are "mutt Khakis" from the bulk hatchery the feed store uses - one called Whelp. They aren't as pretty as those purebreds I had years ago, but I love them them even more. On 11/10/15 I found my first egg, that is about 21 - 22 weeks old for the girls. Since I have not witnessed the actual giving, I don't know which of my girls is the producer of my "duck rounds". They are a little small (would be called 'medium' at today's standards) and I have to wash them. Since she is laying in the same spot I will gradually add bedding and move a few things and hopefully they will stay cleaner. My first flock were inside of a chicken coop and the eggs stayed nicer. This bunch I'm letting free range and simply be ducks, so I'm trying to make a compromise with them to keep the eggs clean.