EU4 Advanced Economics 5. Light Ships

What provinces should you develop? What buildings should you build? Are Manufactories overrated? Should you get a loan or debase currency? These questions are answered over a series of guides. For players looking for nothing less than mathematical precision in their EU4 economy management.

Introduction

Light Ships can be sent on two types of missions:

1. Protect Trade: provides additional Trade Power to the ships' nation in the protected Trade Node. The amount of Trade Power provided by the ships goes up as you unlock more advanced ship types.

2. Privateer: makes the Light Ships act as a dummy nation that collects Trade Value from the privateered Node. The amount collected depends on the Trade Power of each Light Ship, which goes up as you unlock more advanced ship types. A portion of the collected Trade Value is sent to the ships' nation, which appears in the Economy tab as 'Spoils of War'.

The game tooltip displays the expected changes in Trade income as a result of sending your Light Ships on these missions. In this guide, I will investigate whether the displayed values are accurate.

For the necessary calculations, I used an Excel spreadsheet that I developed, which models the behaviours of connected Trade Nodes and quickly calculate changes in Trade income.

Protect Trade

As always, I am using 1 Dec 1444 start date France as an example. France starts with 4 Light Ships capable of providing 2 Trade Power per ship.

At the start of the game, there are 5 Nodes you can protect with your Light Ships: Genoa, Bordeaux, Sevilla, Tunis and Alexandria. You can protect any Node where you have Trade Power.


According to the in-game tooltip, protecting trade at Bordeaux Node is the best choice, giving you a boost of $0.16/month.

It's wrong.


Trust me I have done the maths. Bordeaux is not the best choice. Genoa is.

These are the changes in monthly Trade income when you protect trade in one of the 5 Trade Nodes:

• Genoa: +0.1934
  
• Bordeaux: +0.00363
  
• Sevilla: +0.00977
  
• Tunis: +0.00061
  
• Alexandria: +0.01162
  
• Alexandria Node has a link going to Constantinople which ultimately links to Champagne Node. This means that the actual boost in Trade income from protecting Alexandria Node will be slightly higher than 0.01162. The difference is expected to be negligible, however, so it is ignored.

This is the detailed calculation for Genoa, using my trade simulator spreadsheet:

Some cells do not display any values. This is because Genoa is an end-Node and has no outgoing trade.

Considering that 4 Light Ships cost $0.18/month in maintenance, France does not profit much by protecting trade, at least at the start date. Of course, the value of Light Ships will go up as you invest more in trade-related infrastructures and modifiers.

Now that we know the in-game Protect Trade tooltip is inaccurate, here are some tips on choosing a Node to protect:

• Pick a node where you are collecting or transferring trade with a Merchant. Let your Light Ships help the Merchant collect or steer trade in your favour.
  
• Pick a node with high total Trade Value (Incoming + Locally produced).
  
• If your Merchant is collecting at a non-home Node, that Node should generally be avoided because your Trade Power will receive a 50% penalty there. In the France example, Genoa is the best Node to protect despite having a Merchant collecting trade - this is due to the richness of Genoa Node.

Privateer

In 1444, France has 9 Nodes where it can send pirates to: Genoa, Bordeaux, Sevilla, Tunis, Safi, Alexandria, English Channel, North Sea and Lubeck.


According to the in-game tooltip, privateering at English Channel Node is the best choice, giving you a boost of $0.17/month.

The explanation given by the tooltip is rubbish.



These are the actual boosts in income (recorded as 'Spoils of War' in the Economy tab) when the 4 Light Ships are sent to privateer in one of the 9 Nodes. The exact results will differ in every game.

• Genoa: 0.25
  
• Bordeaux: 0.07
  
• Lubeck: 0.18
  
• English Channel: 0.24
  
• Sevilla: 0.14
  
• North Sea: 0.07
  
• Safi: 0.1
  
• Tunis: 0.06
  
• Alexandria: 0.17

Privateering in either Genoa or English Channel Nodes results in the highest income. In fact, the incomes generated by privateering is overall superior to protecting trade. The Excel table below gives a breakdown of the calculations for the Spoils of War:

• Pirate TP = Trade Power of 4 Light Ships. The formula is: Trade Power per ship (2) x 4 ships x 1.5 (base boost for all privateers) x French Privateer Efficiency (1.009) = 12.108
  
• Collected TV = Total TV x (Pirate TP / Node total TP with pirates)
  
• Spoils of War = recorded manually in my game, after sending the 4 French Light Ships to privateer in one of the 9 Nodes.

Privateer Efficiency of France is displayed in the Trade tab (0.9% in my France example).


There seems to be an error in the way the game calculates Spoils of War. According to EUIV wiki, 40% of Trade Value collected by the pirates should be returned to the player, but in the table above, that figure is closer to 50-55%, not 40%.


There is a mysterious modifier that appears in the tooltip, "The largest Trade Power share in the node makes privateers ... efficient here". This could have something to do with the discrepancy.


If anyone can help me out, please leave a comment.

If there is indeed a fault in the system, it is one that works in the player's favour - the pirates are more powerful than they should be.

Having that in mind, here are some tips on choosing a Trade Node to privateer:

• Pick a Node with high total Trade Value (Incoming + Locally produced).
  
• Pick a Node that contains nations you want to bully, especially your rivals. Pirates collecting trade at a Node means that there are less ducats to go around for other countries in the Node. Privateering a rival's Node also gives you Power Projection.
  
• Preferably avoid a Node where you are transferring or collecting because pirates will lower your own Trade Power share as well.
  
• Check regularly whether the Node you are privateering has ships from other countries, under the 'Hunt Pirates' mission. This will reduce the efficiency of your pirates.

Conclusion

• Protect Trade & Privateering tooltips are misleading and inaccurate.
  
• Since the game tooltip gives the wrong information about where to send your Light Ships, a player needs to figure it out manually. Refer to the above for some tips.
  
• Due to an apparent in-game error, privateering is more powerful than they should be.

Links to the rest of my guides: EU4 Advanced Economics
1. Province development
2. Buildings Part I
3. Buildings Part II
4. Manufactories
5. Light Ships

[forrestomintero]

necro, but this is an important note: privateering also increases power projection. (I think that's only against rivals?) So when you combine multiple privateering bonuses plus great power status, it can be an integral part of maintaining the 50 pp boost to mana generation. which is probably more valuable than money imo.

[Peel]

Perhaps worth adding to the "choosing a Trade Node" section, is that you're looking for a node with a high value to trade power ratio. If the node has 10 value but 100 power, you'll get 1 ducat with about 11 trade power worth, whereas if the node had 5 value but only 10 power it would require only 2.5.

Extra income = V*E/(O+E)
where
V = retained node value (which increases if you add more power and it's not an end node).
E = Effective trade power added (explained well above).
O = Original trade power in the node.

If this was privateering, then take 40% of this for your spoils of war. Otherwise multiply by trade efficiency.

Calculating the increased retained value depends on the outgoing trade power, but is still summarised by best sending ships where there's less existing power present.

[Maccros]

Thanks!

[Stayin Alive]

I loved the wrong in the picture

[Skrymaster]

As far as I've noticed, the bonus to privateering based on the largest nation with share in the node is essentially one of Paradox's attempts to balance out the trade system. Essentially if a nation has an overwhelming portion of the trade power in a node, privateers become considerably more powerful there in response. If a node is not dominated by anyone, privateers are less effective. Generally AI rarely properly(at least by 66%) controls trade nodes, but if by some miracle they do, or if you have a node with 70%+ you'll be likely to notice a lot of privateers there 'till a war breaks out and they get swept, likely because the A.I can tell it's more lucrative to privateer than to protect their own nodes.

[Ugles]

useful stuff thx