Note: 1. The annual precipitation for Japan is the average for the period from 1966 to 1995. The population is according to the 1995 National Census by the Bureau of Statistics Management and Coordination Agency.
2. The annual precipitation for the world and for other countries are based on the documents of the UN Water Conference held in 1977. The population and populations (Mean estimated values for 1986) and measurements are taken from the UN World Statistical Yearbook (1985/86)