I'd be far worried about a seatbelt malfunction locking a child inside an overturned bus or with a vehicular collision where the car is leaking gasoline and has

I'd be far worried about a seatbelt malfunction locking a child inside an overturned bus or with a vehicular collision where the car is leaking gasoline and has the very real potential to catch on fire, which given sufficient heat means there's a very real risk of a diesel fire from the school bus. I'd agree, six deaths a year out of 24 million is acceptable losses by any measure. I'd consider 1 in a million deaths in school busses to be fucking amazing, but 0.25 in a million is absurdly good.