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Japan's service sector accounts for about three-quarters of its total economic output. Banking, insurance, real estate, retailing, transportation, and telecommunications are all major industries such as Mitsubishi UFJ, Mizuho, NTT, TEPCO, Nomura, Mitsubishi Estate, ÆON, Mitsui Sumitomo, Softbank, JR East, Seven & I, KDDI and Japan Airlines counting as one of the largest companies in the world. Four of the five most circulated newspapers in the world are Japanese newspapers. The Koizumi government set Japan Post, one of the country's largest providers of savings and insurance services for privatization by 2015. The six major keiretsus are the Mitsubishi, Sumitomo, Fuyo, Mitsui, Dai-Ichi Kangyo and Sanwa Groups. Japan is home to 251 companies from the Forbes Global 2000 or 12.55% (as of 2013).
Output:
what is the main source of income in japan