NFL Draft value chart revealed!

I have always heard about this mysterious chart that tells NFL officials what each draft pick is worth in points. It rates each pick (not each player) on a 3,000 point system, and is used to determine fair value when trading picks.
For those of you who are interested in these things, here it is.
It's amazing how quickly the value falls off. By the seventh pick, the value of the pick is halved. By the sixteenth pick, the value is at a third.
How do we conclude the seventh pick in any given draft is half as valuable as the first one? I don't know. It would seem to me that the seventh pick is probably something like 23/30 as valuable, and the eighth is 22/30 and so on.
Certainly you could examine the value of the value of the picks in terms of the players picked at the position over the years. But, I can't imagine that all the number one picks have played twice as good as the number seven picks. I'd bet, in fact, they have really been something like 23/30 as good, especially as the sample size gets bigger and bigger.
Maybe someone who has developed a complicated system for keeping a fair and equitable draft order for fantasy baseball could weigh in on the subject.
Regardless of this value chart, the NFL draft is really a calculated crapshoot. Don't let people like Mel Kiper fool you into thinking it's a science.
If it were that easy, there wouldn't be nearly so many experts telling us so many different things.
People who play the slots in Vegas will tell you their system works, too, but there are a lot more bankrupt gamblers out there than empty casinos.