SAGA--Saga prefectural officials are offering food for thought, saying that Tokyo would only have one seat in the Lower House if representation was based on food self-sufficiency rates across Japan. 

The prefectural government, based in Saga, conducted a test calculation that created a controversy over the current situation in which redistribution of electoral districts is discussed solely from the standpoint of vote disparity in terms of relative population size.

Saga suggested that factors other than population sizes, including food and energy production, should also be considered.

Under the simulation, in the Kyushu region in southern Japan, Saga Prefecture would gain three more seats, while Kagoshima Prefecture would have four more. In the Kanto region, Ibaraki Prefecture would have five more seats.

The simulation results were presented by Yoshinori Yamaguchi, governor of Saga Prefecture, at a meeting of the National Governors’ Association in July.

“Various factors, not just population sizes, are essential to the existence of a nation,” Yamaguchi said in citing, among other things, food security and energy production, such as the location of power plants.

“What about taking into account those factors when allocating the number of electoral seats?” he asked by way of a proposal.

Rice, wheat and barley are produced in abundance in Saga Prefecture, most typically in the Saga Plains. The town of Genkai in the north of the prefecture hosts the Genkai nuclear power plant, which is operated by Kyushu Electric Power Co.

The prefectural government simulated how the 289 Lower House seats to be elected from single-seat constituencies would be distributed across Japan's 47 prefectures.

Saga set its sights on the calories to be amassed through the digestion of food and calculated an original indicator called the “calories-based population,” which is the food self-sufficiency rate of a prefecture, according to the farm ministry’s final figures for fiscal 2018, times the population size of that prefecture.

That indicator was subsequently used as a basis for allotting “calories-based number of seats” to Japan’s prefectures by using the "Adams method" formula for the reapportionment of seats in each prefecture according to population fluctuations.

The results were compared with the government’s latest rezoning plan, which involves adding 10 seats and taking away 10 seats in a total of 15 prefectures to lessen vote disparity.

The simulation showed that Hokkaido, the national leader in the self-sufficiency rate at 196 percent, would see its number of seats nearly quintuple from 12 after rezoning, to 59.

All the six prefectures of the Tohoku region would each have five to eight more seats, with Akita Prefecture being the leader. Niigata Prefecture would have nine more seats.

Many prefectures that constitute metropolitan areas, by comparison, would lose significant numbers of seats. Aichi and Saitama prefectures would each have only five seats, both down 11, and Kanagawa Prefecture would be represented by only two, down 18.

Tokyo and Osaka Prefecture, the joint tailenders in self-sufficiency rate at only 1 percent, would each be represented by only one seat. That would be down 29 for the Japanese capital and down 18 for Osaka Prefecture.

The latest trial calculation is based not on output values but on calories, so it tends to give high marks to areas that produce large volumes of farm products that serve as the staple diet, such as rice, wheat and barley.

The idea resembles the “kokudaka” system of early-modern feudal Japan, where the productivity of a province was represented in units of “koku,” supposedly about equal to the amount of rice consumed per single adult per year.

Under the kokudaka system, various quantities, including the output volumes of farm products other than rice and of marine products, were also converted to koku units to represent the overall productivity of a province.

The measurements were also used to assess the strengths of feudal domains. For example, the Saga Domain, based at Saga Castle in the eponymous city, was assessed at 357,000 koku, whereas the Kaga Domain, which ruled over the whole of present-day Ishikawa and Toyama prefectures, was assessed at about 1 million koku.