Calculation of state incomes in SOW

Incomes of states are calculated in three steps. In the first step, the effectiveness of blockades and embargoes is determined. In the second step, each city receives income based on its level, whether it is native-owned or not, hostile land units in its area, and if it is a port, any blockades or embargoes in effect and commerce raiding in its waters. In the third step, trade lost to blockades and embargoes is redirected to other ports as merchant captains seek to trade in alternative locations.

In the first step, blockade and embargo effects are determined for each state. The percent of port trade lost to a blockade is the total port levels of the blockaded ports of a nation divided by the total port levels of the nation, times one-half. Germany is one nation for the purpose of this calculation, and so is Italy. Example: France has 11 ports with a total of 37 levels. If Brest, Cherbourg, Le Havre, and Boulogne are blockaded (total of 14 levels) then France loses (14/37)*(1/2) = 18.9% of its port trade to the blockade. A nation loses half of its port trade if all of its ports are blockaded. The percent of port trade lost to embargoes is equal to the fraction of a nation's trade with the nations it is embargoing. Example: Prussia has 3 ports with a total of 12 levels, but only controls 2 of them with a total of 8 levels. Prussia is embargoing France and Russia. 13.0% of Prussia's trade is with France and 13.7% is with Russia. Prussia loses 13.0%+13.7% = 26.7% of its port trade to the embargo.

Blockades and embargoes cause both direct losses and indirect losses to the trading partners of the nations being blockaded or embargoing.  For a blockade, the direct loss affects the side controlling the blockaded port and the indirect losses affect its trading partners. Example: If France loses 200 Cr of income to a blockade, then since 18.4% of France's trade is with Britain, Britain loses 200*18.4% = 37 Cr of income indirectly. Since 5.3% of French trade is with Prussia, Prussia loses 200*5.3% = 11 Cr of income indirectly, and similarly for all other nations. Indirect losses to nations with more than one state are divided between the states in proportion to the port levels they control. Example: Germany has 4 ports with a total of 15 levels, of which Hannover controls Bremen with 4 levels and Mecklenburg controls the rest. Since 7.9% of French trade is with Germany, Germany loses 200*7.9% = 16 Cr of income indirectly. Hannover loses 4/15 of this or 4 Cr, and Mecklenburg loses 11/15 of this which is 12 Cr.

In the second step, incomes are determined for each city and off-map port. A city's base income is 20 times its economic level if inland and 24 times its level if a port. The base income is modified in several ways, with all modification being percentages and being cumulative (that is, if income is reduced 40% in one step and increased by 10% in another, the net reduction is 34%.) First, cities lose 5% of their income for each hostile unit within 4 squares up to a maximum of 20%, plus 5% of their income for each city within 8 squares that is embargoing them, up to a maximum of 20%, for a total modification of at most 40%.

Next, if the city is not controlled by a native state (one of the nation the city is located in) then its income is cut by 50%.

Next, if a port city controlled by a native state is blockaded, it loses 50% of its income. If a port city is not blockaded, then if other ports of its nation are blockaded, it gains income through trade shifted from the blockaded port. Example: France has 11 ports with a total of 37 levels, and Brest, Cherbourg, Le Havre, and Boulogne are blockaded (total of 14 levels). Income in the four blockaded cities is reduces by 50%, which is 24*14*0.5 = 168 Cr. However, total port income is reduced only by 24*14*0.189 = 64 Cr. The remaining 104 Cr is distributed to the unblockaded ports, and each port gets an increase of the total port levels of the blockaded ports of a nation divided by the total port levels of the nation, times one-half. Example: with 14 French port levels blockaded out of 37 total, each unblockaded port gets a bonus of (14/37)*(1/2) = 18.9% to produce the appropriate net loss from the blockade.

Next, if a port city controlled by a native state is embargoing other states, it loses the relevant fraction of its income. Example: If Prussia is embargoing France and Russia, then if Prussia controls Danzig, then Danzig loses 26.7% of its income.

Last, if a port city, it loses income to raiding; the percentage is raiding strength divided by the sum of raiding strength plus convoying strength plus 12. See SOW rule 2.7 for the calculation of raiding and convoying strengths at a port.

The calculations are somewhat different for off-map ports. At off-map ports, base income is 28 times the economic level of the port. This is reduced by 25% if the port is not controlled by its original owner. If the port is blockaded, it loses 50% of its income, and indirect losses are 30% to the owning state, 10% to Britain and 5% each to Holland and France. If the port owner is embargoing Britain, the port loses 10% of its income, and if the port owner is embargoing France or Holland, the port loses 5% each. The embargoed nation loses the same amount in indirect losses. Commerce raiding is applied according to the same formula as for on-map ports.

In the third step, direct losses from blockades and embargoes are redirected to other nations. The direct losses suffered by each nation in the first step are shifted to other nations and their trading partners according to the trade shift chart. Example: If France has 500 Cr of direct trade loss from blockades and embargoes, then 20% of this trade, or 100 Cr, is redirected to Britain, and 100 Cr is distributed to Britain's trade partners, so that 13.0% (in this case, 13 Cr) go to Holland, 10.3% (10 Cr) go to Spain, and so forth, with 19.6% (20 Cr) redirected back to France. These gains are modified by blockade and embargo percentages, so that if France had 14 of its 37 levels blockaded, it would lose 18.9% of its redirected gains, so that its gain would be 16 Cr rather than 20.
Last modified December 8, 2009