Caravan initial income and turn based trade formula

Hi all,

been a year (or probably more) since i last visited the forums,
just got back into civ 1 again and was using caravans to boost the trade (as many do)

I recall seeing in the past something related to this topic where the initial income and turn based trade boost is related to both distance, trade value of both cities involved and if the target city is owned by the PC or not.

I am simply assuming the formula for this is already known to the forum, unfortunately I was looking around without any luck, so decided to ask if such formula is available could someone forward me to the topic please ?

i dont think this formula is dependent on dificulty, but if it is, i play mostly chieftain, warlord and rarely prince. (i like easy victories lol)

The formulas are documented in "Rome on 640K a Day".
Caravan Arrival Bonus = (Distance+10)*(TradeA+TradeB)/24
Bonus is divided by 2 if both cities are on the same continent.
Bonus is divided by 2 if both cities belong to the same civ.
Bonus multiplied by 2/3 if both civs have railroad *.
Bonus multiplied by 2/3 if both civs have flight *.
The bonus penalties are cumulative.

* The book says the railroad and flight penalties kick in when YOU discover them. In my experience, the penalties kicked in when the AI discovers railroad/flight.


Trade from the established route:
Trade = (TradeA + Trade B + 4) / 8
Trade is cut in half if both cities belong to the same civ.
So distance, same continent and tech level don't affect the ongoing trade benefit.

thanks for the clarification.

Thanks for the pro-tip!