I should have made it clearer that this is just a sanity check. I find the rough approximation 30 million seconds in a year often comes in handy for back of the envelopers like this. 10 seconds thought was all it took to check that 2 people dying every second is at the very least reasonable.
Well 7/3 = 2 (more or less - the whole calculation is very approximate obviously). The basic idea is if you have 100 people (of a broad spectrum of ages) you'd expect about 1 of them to die each year.