I've been playing SWC for some 3 years now, and I have never gotten this:
When you create your character, as I have 4 times had to do, you always start out with a different amount of credits. Why is this? Is it perhaps the day you create your character? Maybe it is a skill or something?
As Ten said. The value was also increased around a year or so ago so that it at least covered the longest NPC travel between homeworlds and an item or 2 from the NPC shop.