Each center of trade has a trade value, in ducats, which is the sum of the generated trade in all provinces which are part of the center of trade's trading area. The trade value of the center of trade is shown on the center of trade screen, and also on the main map when it is in trading map mode. Although trading income is computed monthly, the displayed trade value is the yearly figure that would be generated if everything stayed as it currently is at the time. The monthly amount of trade is the displayed figure divided by 12.