Raynor's right about the formula. Basically you have to add the % increase for happiness, planet population, and race settings first, then multiply in. Planet and system facilities are multiplied separately.
From this it's obvious you have some diminishing returns on the race modifications. If you want to maximize your total, increasing planet value is much more important.
Nice to see you're getting some use from the save file, Raynor. I hope I didn't knock myself out of the top 4 spots posting all this stuff, I'd hate to not recoup the price of the game.
[This message has been edited by Drake (edited 18 February 2001).]