Hmm tried to made an Excel but it is not accurate (G&K).
I am interested in a proper formula because I placed my cities perfectly (which means 6 hexes between them so they never overlap) thus requiring 6 maintenance per turn for 1 connection (x2 cities@ start).
I started with a small loss of 2 gold per turn. Eventually my cities grew and my income increased to 27 gold per turn (-12 roads). After that I conquered two additional cities that had a road connection between them, and founded another city to link them. Added a road to this (11x+3x from captured). Now my trade income rocketed to 47 gold per turn (!).
Situation now:
5 connected cities
capitol 15
cities: 12,10,5,8,6
income: 50
expenses: 26
Any tips?
edit: Almost there.
I did not understand from your post that the 0.15 x population of capitol is added for EACH city and the -1 is also per traderoute.
Thus: =Size*1,1+SizeCapi*0,15-1=14,45.
This matches the game perfectly.
Issue:
12,25
14,45
10,05
6,75
7,85
This adds to 51.35 (all match game)
Game adds them as 50.25
How is that difference explained?
ps Proper formula=
=B1*1,1+(C1*0,15)*D1-(D1*1)
=PopluationCities*1,1+(Capitol*0,15)*cities-(cities*1)
Note that populationcities=total population of all cities connected to the capitol and cities is the number of cities connected TO the capitol.