The inner workings of the Demo screen explained

[Revent]

Just discovered these numbers myself. Great thread by the way.

So i should not worry if its negative? I have very low number, but are the biggest one on the map. But that only means that the others civs have more trade routes with me, than i with them?

Is there a limit to number of trade routes? I never use mercantilism, but i should switch to that when negative number? (if i make 10 gold, and the others civs make 20 gold my number will be -2. If i stop trading i lose 10 gold, but the others lose 20 gold?)

You should able to use that 10 commerce much more efficiently than the AI though

 

[T-hawk]

(if i make 10 gold, and the others civs make 20 gold my number will be -2. If i stop trading i lose 10 gold, but the others lose 20 gold?)

Basically yes. (Your number would be -10, not -2).

Although it's not always that perfectly simple. If you stop trading (close borders or go Mercantilism), you lose 10 commerce and the other civs lose 20 commerce in trade routes to you. But some of that will be replaced with domestic trade routes to each civ's own cities, or perhaps even more foreign routes if more cities exist belonging to other civs. It's not something that can be figured simply with a single plus-or-minus number, but you can get a general idea.