It’s definitely not the chance of death in a year of swimming. My link already gives us all the numbers we need to calculate that—the number of deaths overall, the number of years being examined, and an estimate of the population involved—and it comes out to a chance of 1 in 5,658. (1,754,182 people / (31 deaths / 10 years).)
This conveniently lets us infer how they’re probably calculating the risk—it looks like they’re assuming one hundred sessions per year (or about two a week; fair enough) and doing a per-session estimate based on that. I also notice that the population estimate is identical to that for cycling and running, so it’s probably some sort of estimate of the number of people in Germany involved in an arbitrary popular sport. Cruder than I’d like, but I was only shooting for an estimate good to within an order of magnitude.
It’s definitely not the chance of death in a year of swimming. My link already gives us all the numbers we need to calculate that—the number of deaths overall, the number of years being examined, and an estimate of the population involved—and it comes out to a chance of 1 in 5,658. (1,754,182 people / (31 deaths / 10 years).)
This conveniently lets us infer how they’re probably calculating the risk—it looks like they’re assuming one hundred sessions per year (or about two a week; fair enough) and doing a per-session estimate based on that. I also notice that the population estimate is identical to that for cycling and running, so it’s probably some sort of estimate of the number of people in Germany involved in an arbitrary popular sport. Cruder than I’d like, but I was only shooting for an estimate good to within an order of magnitude.