How exactly does Protecting Trade Work?

[Angry Soviet]

Playing as Venice, and I'm trying to understand this mechanism.

Have a huge fleet of barques, when I mouse over protecting trade in Alexandria, it says "this will bring your total profit up by 6.68 ducats, which sounds very nice. However, when I actually send my fleet to patrol in the Alexandria trade node, it boosts up my income from 10 ducats per month to only 11. Why is this happening? How does the protect trade system work?

Thank you!

[Dreamers]

Protecting trade increases your trade power in that node, that's all.

To start simply your initial trade income comes from collecting in your home node(where your capital is) which is Venice in this case, there the calc is how much is the trade node worth(trade value) and how much of the total trade power you own then the modifiers are applied.

An example is that if you have 50% of the trade power and the trade value is 10 you get a base income of 5 then modifiers are applied over it. Thus if you increase trade value in Venice you get more income.

In your case what you are seeing is that the system shows how much of the trade share you influence but to actually get it you need to either collect with a merchant in Alexandria* or place a merchant there to steer trade on to Venice where you are collecting it.

Give a read on the page in the wiki here[www.eu4wiki.com] and ask anything you don't understand. Also don't be afraid to play with merchants and ships to understand things better.

*Generally not worth doing that since collecting outside your home node has a penalty on trade power.

[Kagemin]

If you send a fleet to protect trade you will get a flat amount of trade power per light ship.
A trade node has a total value, made up of trade steered there from upstream trade nodes and goods produced in that node.

Depending on their trade power every nation taking action in that node (steering trade or collecting) will get a certain amount of value of the total in that node. It's a direct percentage of the percentage of trade power a nation has in that node, but there are a couple modifiers to your trade power (mercantilism, overextension, etc).
So sending light ships to protect trade in a node is a good way to increase your power in that node, directly resulting on more income depending on what you do with your power.

Depending on the trade power you have in the Venice node it can be better to steer more trade there from the Alexandria node (if you have a lot of power in Venice), or collecting directly from the Alexandria node (you get a penalty for that, but if you have a ton of power there and the Venice node is contested it can still be better).

As for the difference between what the tooltip said and the actual increase in income, that depends on wether you're collecting trade in Alexandria or steering trade there.
If you're steering trade to Venice it's so much less because you don't collect 100% of the value in Venice. You may steer 6.6 ducats more to Venice, but because the node there is contested you only actually collect part of it.
If you are collecting in Alexandria, I think the tooltip doesn't take into account the penalty for collecting in foreign trade nodes. Not 100% sure on that one though.


Iirc there is a pretty good guide on trade here on Steam, might be worth it to check that out. Plus you can of course ask if there's anything unclear.

[Angry Soviet]

Wow thank you guys, very helpful answers! I think I get the idea now.

One more question: when you say a trade node is contested, to what degree do you mean? For example, I have around 75% control of my home node in Venice, I don't know if I should go for 100% or try to send my lightships to other areas to steer.

[Kitten Food]

75%-80% is good. You can just open up the trade node to see how the money is being split among other nations. Trying to get to 100% just through ships will end up being less profitable than collecting in other rich nodes that you can send light ships to. Just remember to keep building trade power buildings in your major trade ports at home. This will allow you to reduce the amount of ships needed at home to keep power around 80%.