This wikipedia page is an example of an export trading treemap developed by the Observatory of Economic Complexity of MIT Media Lab and the Center for International Development at Harvard University. It show Malawi export product percentages in coloured coded treemap.
Haussmann, R. Hidalgo, C, et. al (2013) Malawi Exports Treemap, Electronic Complexity Observatory, MIT Media Lab and the Center for International Development at Harvard University. Retrieved from: https://en.wikipedia.org/wiki/File:Malawi_treemap.png
For more examples see The Observatory of Economic Complexity