Furthermore, how do you calculate overheads for a power?
Overheads are calculated based on the number of control systems that a power has. It's slightly complicated, but I'll explain it in detail.
Overheads = MIN{ (11.5 * Number_of_Control_Systems / 42)^3 ; 5.4 * 11.5 * Number_of_Control_Systems }
We need to calculate two values to get the end result.
Small Power overheads = (11.5 * Number_of_Control_Systems / 42)^3
Large Power overheads = 5.4 * 11.5 * Number_of_Control_Systems
It turns out that at 55 control systems, these two end up within 1 CC of each other, which is why people talk about the 55 control system cut off.
Why 11.5, why 5.4, why 42?
11.5 is what FDev decided to use as the average number of exploited systems for each control system.
5.4 is what FDev decided to use as the average CC income for each exploited system.
42 is the answer to the ultimate question according to The Hitchhiker's Guide to the Galaxy (I've honestly no idea if this is the actual reason though).
This formula results in two things:
1) Small powers (less than 55 control systems) pay less overheads per control system, but as they inch closer to the cutoff point, their total overheads increase quite a lot with each system, as every system's overheads increase every time. I don't remember the actual numbers, but let's assume for a moment that the overheads per control system at 50 and 51 systems increases from 50 to 51 CC, then getting number 51 will increase the overheads from 2,500 (50 * 50) to 2,601 (51 * 51) - an increase of 101 CC
2) Larger powers (55 control systems or more) pay the maximum fixed overheads per control system (62.1 CC), but this is a far more predictable, as the total overheads always increases by 62.1 CC rather than massively increasing.
