[Influence]

It is more profitable to have an FC(compared to a ref) when 0.5% of a planets base income exceeds the income you get from a ref, which is 1100+(1100*bonus).

Let's assume you are comparing a corp planet that has 0 FC's (so with 49% bonus). Base income is direct income without any bonus from mining/refs/roids.

So 0.5% of your base income should exceed 1100 + (1100 *0.49) which is 1639. that meas your base income should exceed 1639/0.005 which is 327800.

Let's assume you are comparing a planet that has Magma done, which accounts for 75000 of the base income. That means you still have to get 252800 resources from roids and refs. A roid gives 250 resources in base income so you need 1011.2 roids for a FC to be more profitable than a ref. A refinery gives 1100 resources in base income which is 4.4 times that of a roid. That means for each refinery you allready have you can substract 4.4 roids.

That means in this situation a FC gives more income when you have at least 1011.2-(4.4*number_of_refs) roids.

The problem with determining the exact number of roids you need in which situation lies in the fact that each FC you have increases the income a ref gives by 5.5 resource which in turn means you need another 4.4 roids(or 1 ref) per FC you have for the next FC to yield more income than a ref.

P.S. i have a flue while writing this so my math may be off here and there.