Primary sector of industry in the context of "Secondary sector of the economy"

Agriculture, forestry, and fishing (Japanese: 農林水産, nōrinsuisan) form the primary sector of industry of the Japanese economy together with the Japanese mining industry. Together, they account for 1.3% of gross national product; only 20% of Japan's land is suitable for cultivation, and the agricultural economy is highly subsidized.

Agriculture, forestry, and fishing dominated the Japanese economy until the 1940s, but thereafter declined into relative unimportance (see Agriculture in the Empire of Japan). In the late 19th century (Meiji period), these sectors had accounted for more than 80% of employment. Employment in agriculture declined in the prewar period, but the sector was still the largest employer (about 50% of the work force) by the end of World War II. It was further declined to 23.5% in 1965, 11.9% in 1977, and to 7.2% in 1988. The importance of agriculture in the national economy later continued its rapid decline, with the share of net agricultural production in GNP finally reduced between 1975 and 1989 from 4.1% to 3% In the late 1980s, 85.5% of Japan's farmers were also engaged in occupations outside farming, and most of these part-time farmers earned most of their income from nonfarming activities.

In economics, the Prebisch–Singer hypothesis (also called the Prebisch–Singer thesis) argues that the price of primary commodities declines relative to the price of manufactured goods over the long term, which causes the terms of trade of primary-product-based economies to deteriorate. As of 2013, recent statistical studies have given support for the idea. The idea was developed by Raúl Prebisch and Hans Singer in the late 1940s; since that time, it has served as a major pillar of dependency theory and policies such as import substitution industrialization (ISI).