My only adult experience with ducks (had Mallards at home when I was a kid) is with runners. They -- and most of the chickens -- have stopped laying for the year, but were really productive all spring and summer. I was usually getting five to six eggs a day from my seven girls.
Some breeds do tend to lay more then others, however a lot of it will come down to environment, nutrition, location etc. I've had Runners, Rouens, Mallards and Hookbills. My Hookbills pretty much lay all year round. Last winter the only time I didn't get at least 1-2 eggs a day during the winter was when we moved, but after 2 weeks of settling in even though it was in February my Hookbills started to lay again.