kokudaka

refers to a system for determining land value for taxation purposes under the Tokugawa shogunate of Edo-period Japan, and expressing this value in terms of koku of rice.

One (roughly equivalent to five bushels) was generally viewed as the equivalent of enough rice to feed one person for a year. The actual revenue or income derived from a holding varied from region to region, and depended on the amount of actual control the fief holder held over the territory in question, but averaged around 40 percent of the theoretical .