That's 1 in 2000 of the entire population. 1/100,000th of the US population drowns every year, which means that 1% of drownings has an annual incidence of 1/1mi

That's 1 in 2000 of the entire population. 1/100,000th of the US population drowns every year, which means that 1% of drownings has an annual incidence of 1/1million. (This is annual vs lifetime but if you do the rough math under some basic assumptions, you end up easily within what you're defining as "rare")