It's 198 - ( 14 x ( countOfHumanPlayers - 1 ) ). However, then many ships have with an overall multiplier against that, typically ranging from 0.1 to 2.0 or so. Though in the case of things like mines, I think it's actually 5.0. And there are a very few ships with an overall fixed ship cap of something low, like 5 or 9 or similar (I think fortresses, and a few other things like that).