Yes, you're right, it would be very useful information to know. But the rules don't require it, and as far as I know the NTSB doesn't track it. Here's as close as they come:

Quote:

NTSB Part 830.5 Immediate Notifciation

The operatore of an aircraft shall immediately, and by the most expeditious means available, notify the nearest NTSB field office when:

(a) An aircraft accident or any of the following listed incedents occur:

<snip>

(7) For large multiengine aircraft (12,500 lbs)

<snip>

(iii) Sustained loss of the power or thrust produced by two or more engines


The NTSB doesn't track a lot of minor aircraft incidents that could be early indicators of safety trends. They don't even track total hours flown for general aviation, which would make the rest of their accident data a lot more meaningful. For example Cessna shows up a lot in the accident data. They have no data about how many hours cessnas are being flown. Does that make Cessna a bad airplane? Well, of course not, there are a lot of Cessnas out there.
_________________________
- Benton