We didn't have any type of filters on these calls. We got a lot of bad data.

But every day, too, we get one or two we can't find anywhere — truly missing people, whose absence has only now been discovered.

We tracked one parolee to New York, but when we got him on the phone he threatened to kill the person who found him.

Of the almost 1,500, we suspect there's a 'nugget' who are truly missing ? washed out into the Gulf. Then there's a small subset that honestly don't want to be found. How do we know when we're done? How long do you keep looking? What do you do when you've done all the DNA testing you can, when you've called everyone and you still can't find the person?

What that final number will be, we're trying to come up with a methodology to estimate that. It could be that several hundred people were either washed out to sea or crushed beneath buildings or otherwise are just not locatable.

We've found quite a few people who didn't want to be found.