The effect of railroad and other techs on trade

[Salaambo]

Many people know that the discovery of navigation or invention will half the trade you get from caravans.

But are people also aware that railroad will also decrease trade from caravans by 1/3rd? This happens both in combination with navigation and invention or without it.

Also, i have been experimenting with caravans in cheat mode, giving and removing techs and testing the results. I have found that in ALL games railroad will decrease caravan trade by 1/3rd, but ONLY IN SOME GAMES will navigation or invention half the trade from caravans.

It must be that the discovery of navigation and invention only decreases the caravan trade when some other tech has not been discovered or some other wonder has not been built. But what is it? I have tried Adam Smiths and Economics, its not that, I have even tried removing all techs from every civilization in the game and giving them navigation and it still will not half the trade.

Anybody know the answer to this mystery?

[rjmatsleepers]

Do you mean caravans alone, or are you including freight? I don't recall noticing this with freight deliveries. In anycase, railroad increases the rate at which you can deliver freight so significantly that there is a net benefit.

RJM

[Magic_gorter]

I guess Salaambo is the same as Wildpony on CFC...

He now knows the answer...it happens after turn 200... before that turn there is no "penalty".