Age of Empires III: The Asian Dynasties followed a similar format to the original game, Age of Empires III. Rather than introduce new methods of gameplay, most changes were focused on introducing new content to the game.
Export is a special resource, only available to the three Asian civilizations, and is used to hire foreign troops and research technologies from the consulate, where the player can choose a foreign ally or, for the Japanese, isolationism. Export is generated automatically when the villagers are gathering, but its gather rate is much slower than other resources, making it challenging to afford a large foreign army. Export Rate / Experience points are also generated by other means (like sacred cows for Indians) and are specific to each clan.
This article uses material from the Wikipedia article Age of Empires III: The Asian Dynasties, https://en.wikipedia.org/wiki/Age_of_Empires_III:_The_Asian_Dynasties which is released under the Creative Commons Attribution-Share-Alike License 3.0, https://creativecommons.org/licenses/by-sa/3.0/.