It is well known that the precipitation and the temperature during the spawning season of sweetfish affect the catch in the next year. There should be the favourable precipitation for the catch as well as the favourable water temperature for sweetfish. The method evaluates the catch from the precipitation and the temperature during the spawning season of sweetfish considering these phenomena. This method is also an excellent prediction method of the catch of sweetfish, because the precipitation and the temperature can be easily obtained.
