How exactly is Force Requirement tonnage calculated?

[dizzy]

From the manual: Nations are required to have a minimum naval presence in each area where they have possessions. This is expressed as a
tonnage required in each area, and is dependent on the number and value of the possessions owned by the nation.



I have changed the value of the possessions of a nation, but the Force Requirement of a region did not change. Why?

[aeson]

Note that the following is specifically for Very Large fleet sizes, and is a guess as to how things work based on observed tonnage requirements; requirements on other fleet sizes may differ.

- Home sea zones and sea zones which would require less than 3,000 tons on station do not have a station tonnage requirement.

- Typical station tonnage requirements appear to be 1,000 tons per point of colony value held in the sea zone.

- Some sea zones have a modifier applied affecting the station tonnage requirement - Northeast Asia (4.5 times normal station tonnage requirement); North American West Coast, South Pacific, and North Pacific (0.5ish times normal station tonnage requirement); The Mediterranean (2.25ish times normal station tonnage requirement) - which is applied before the check for the 3,000t minimum.

- There appears to be some nonlinearity with very high possession value held in the sea zone, as can be seen with several UK stations (South Pacific, Southern Africa, Indian Ocean).

I cannot guarantee that this is a perfectly-accurate summary of how station tonnage requirements are computed, but that is how it appears to work to me.

Also, for the unmodded game on Very Large fleet size, a summary of station tonnage requirements and possession value held by power and sea zone:

Green indicates a home sea zone; the black box with red font indicates the average tonnage required per point of colony value excluding colonies in sea zones which do not have station tonnage requirements whereas the line above shows the same including colonies in sea zones which do not have station tonnage requirements.

[dizzy]

Ok, that's a pretty cool chart! Looks like the US and UK are getting a break. I did some interesting things with the mapdata file. I took away some home areas. For example, Russia had their build area moved to Northeast Asia and their former Home Area in Northern Europe was taken away and it forced on them an 11,000 ton force requirement. But no matter how I adjusted the possession value of the colonies in that area, I could not alter the force requirement. Strange. Trying to figure it out. You could always alter mapdata and see what it would affect.