I am curious if anyone can answer this for me or an in depth analysis has been done that someone can point me to.

I understand that Economic starbases give a bonus % to income on trade routes within thier area of effect (assuming you have installed the proper modules). Is this bonus limited only to trade routes originating from your civilization or does it include trades ending in your civ from another empire? Also, if a trade route runs through your empire from Civ A to Civ B (not to or from one of my own planets) can the economic starbase net you a percentage of that trade route's profit, something like a tariff?

I used heavily upgraded econ starbases in my first successful game, and they seemed to increase my trade more than I thought they should. My current game is as a custom race called the Haktoth and I am sandwiched between the Terrans, Drath and Iconians all of whom have trade routes with each other running through my area of influence. I was looking to capitalize on thier routes if econ bases function as tariff collectors as well.