Yeah, that makes sense. The US annual death rate is 8.39 per 1000[1]. The newest ship in Carnival's inventory holds up to 3,690 passengers[2]. I can't find crew capacity, but some googling suggests there ought to be more than 1000 crew on a loaded cruise that size.

So if you're floating around with 4690+ people, naïvely, about 39 people should die on it every year, or one every 9.28 days.

On a 10-day cruise of that size, somebody is going to die. I bet once you control for the unusually high average age of the passengers and maybe other factors (how many drunken idiots fall over the side and drown every year?), 3 people in 10 days would be pretty normal.

[1]https://www.cia.gov/library/publications/the-world-factbook/...

[2]http://en.wikipedia.org/wiki/Carnival_Breeze

The drunken idiots falling over the side and drowning don't usually get found. As far as I remember, the odds of being found after falling off a cruise ship are really low.