[raynor]

For most races it is 1000% or 10x their score. For example, take a look at the Abiddon file in pictures\races\Abbidon\Abbidon_AI_Politics.txt

Score Percent To Accept Demand your surrender := 1000

A couple of the races such as the Amon-Krie have a line that looks like this:

Score Percent To Accept Demand your surrender := 5000

So, they require 50!! times their score before they will surrender.

If you asked the Amon-Krie to surrender, even one ship outside that system *might* have been enough to give him a score so that you didn't beat his by fifty times.