We start a game. Difficulty level does not matter I think. We SIP by a river and work a floodplain while building a worker. We select and de-select a tech at the start of every turn (i.e. put no to any tech until T5), then we choose agriculture and end turn. If you already weren't doing this, start doing it for reasons that you will soon understand. So we have generated 10 every turn. How much is put into agriculture after we click end turn? Expectation: Spoiler : 66. On T6, we have researched for 6 turns since the game starts T0. You get one extra every turn no matter what your slider position is. So 6*10+6=66. Reality: Spoiler : That is correct. What if on T5 we meet an AI that already has agriculture? There is a hidden +5% bonus for every AI that knows the tech you are researching. Expectation: Spoiler : 6*10*1,05+6=69 Reality: Spoiler : 68. Anyway, you've just won 2 by select/de-select and meeting an AI. Congratulations. Meet two guys that have agri: Spoiler : Expectation 6*10*1,1+6=72, reality 70. Same goes on when adding more met civs, you get 2 less than expected, until you've met 6. Expecting 6*10*1,3+6=84, reality 81 so now the difference is 3. Can anyone explain why and what the correct formula could be? I double checked my tests and there doesn't seem to be any human error. Maybe code diving is required, but that is something way beyond my abilities. Then there is the 20% bonus per pre-requisite that I also want to investigate. Based on my previous experience it is not additive with 5% bonuses, but calculated separately.