Planet and Atmosphere Percentages

[Suicide Junkie]

That is for Vaccuum breathing races with gas colonization tech. Admittedly, it is very rare to have as a starting setup, but it is possible with the right mod.

More relevant, your vaccuum breathers will eventually develop gas colonization tech, so those numbers will definitely become important in the mid-late game period.


Specifically;
The numbers you see are the average value of one starsystem to a race with that atmo and surface type.
If the race has two or three surface types available, you can add the numbers together.