The Nikkei average is the most watched index of asian stocks. It has been calculated daily by the Nihon Keizai Shimbun newspaper since 1971. It is a price-weighted average (the unit is Yen), and the components are reviewed once a year.

As of January 2003, the Nikkei 225 consists of the following companies:

• Advantest Corporation
• AEON CO., LTD.
• Ajinomoto Co., Inc.
• All Nippon Airways Co., Ltd.
• Asahi Breweries, Ltd.
• Asahi Glass Company, Limited
• Asahi Kasei Corporation
• The Bank of Yokohama, Ltd.
• Bridgestone Corporation
• Canon Inc.
• CASIO COMPUTER CO., LTD.
• The Chiba Bank, Ltd.
• Chiyoda Corporation
• Chubu Electric Power Company, Incorporated
• Citizen Watch Co., Ltd.
• Clarion Co., Ltd.
• Credit Saison Co., Ltd.
• CSK Corporation
• Dai Nippon Printing Co., Ltd.
• Daiichi Pharmaceutical Co., Ltd.
• Daikin Industries, Ltd.
• Dainippon Pharmaceutical Co., Ltd.
• Daiwa House Industry Co., Ltd.
• Daiwa Securities Group Inc.
• Denki Kagaku Kogyo Kabushiki Kaisha
• DENSO CORPORATION
• DOWA MINING CO., LTD.
• East Japan Railway Company
• Ebara Corporation
• Eisai Co., Ltd.
• Fanuc Ltd.
• Fuji Electric Co., Ltd.
• Fuji Heavy Industries Ltd.
• Fuji Photo Film Co., Ltd.
• Fujikura Ltd.
• Fujisawa Pharmaceutical Company Limited
• Fujitsu Limited
• Furukawa Co., Ltd.
• The Furukawa Electric Co., Ltd.
• Hazama Corporation
• Heiwa Real Estate Co., Ltd.
• Hino Motors, Ltd.
• Hitachi, Ltd.
• Hitachi Zosen Corporation
• Hokuetsu Paper Mills, Ltd.
• Honda Motor Co., Ltd.
• Isetan Co., Ltd.
• Ishikawajima-Harima Heavy Industries Co., Ltd.
• Isuzu Motors Limited
• ITOCHU Corporation
• Ito-Yokado Co., Ltd.
• Japan Airlines System Corporation
• The Japan Steel Works, Ltd.
• Japan Tobacco Inc.
• JFE Holdings, Inc.
• Kajima Corporation
• Kanebo, Ltd.
• The Kansai Electric Power Company, Incorporated
• Kao Corporation
• Kawasaki Heavy Industries, Ltd.
• Kawasaki Kisen Kaisha, Ltd.
• KDDI Corporation
• Keio Electric Railway Co., Ltd.
• Keisei Electric Railway Co., Ltd.
• Kikkoman Corporation
• Kirin Brewery Company, Limited
• Kobe Steel, Ltd.
• Komatsu Ltd.
• Konica Corporation
• Koyo Seiko Co., Ltd.
• Kubota Corporation
• Kumagai Gumi Co., Ltd.
• Kuraray Co., Ltd.
• Kyocera Corporation
• Kyowa Hakko Kogyo Co., Ltd.
• Marubeni Corporation
• Marui Co., Ltd.
• Matsushita Electric Industrial Co., Ltd.
• Matsushita Electric Works, Ltd.
• Mazda Motor Corporation
• Meidensha Corporation
• Meiji Dairies Corporation
• Meiji Seika Kaisha, Ltd.
• Mercian Corporation
• Millea Holdings
• MINEBEA CO., LTD.
• Mitsubishi Chemical Corporation
• Mitsubishi Corporation
• Mitsubishi Electric Corporation
• Mitsubishi Estate Company, Limited
• Mitsubishi Heavy Industries, Ltd.
• Mitsubishi Logistics Corporation
• Mitsubishi Materials Corporation
• Mitsubishi Motors Corporation
• Mitsubishi Paper Mills Limited
• Mitsubishi Rayon Company, Limited
• Mitsubishi Tokyo Financial Group, Inc.
• Mitsui & Co., Ltd.
• Mitsui Engineering & Shipbuilding Co., Ltd.
• Mitsui Fudosan Co., Ltd.
• Mitsui Mining & Smelting Co., Ltd.
• Mitsui O.S.K. Lines, Ltd.
• Mitsui Sumitomo Insurance Co., Ltd.
• Mitsui Trust Holdings, Inc.
• Mitsukoshi, Ltd.
• Mizuho Asset Trust & Banking Co.
• Morinaga & Co., Ltd.
• Nachi-Fujikoshi Corp.
• NEC Corporation
• NGK INSULATORS, LTD.
• Nichirei Corporation
• Nikko Cordial Corporation
• Nikon Corporation
• Nippon Express Co., Ltd.
• Nippon Flour Mills Co., Ltd.
• Nippon Kayaku Co., Ltd.
• Nippon Light Metal Company, Ltd.
• Nippon Mining Holdings, Inc.
• Nippon Oil Corporation
• Nippon Sharyo, Ltd.
• Nippon Sheet Glass Company, Limited
• Nippon Shinpan Co., Ltd.
• Nippon Soda Co., Ltd.
• Nippon Steel Corporation
• Nippon Suisan Kaisha, Ltd.
• Nippon Telegraph and Telephone Corporation
• Nippon Unipac Holding
• Nippon Yusen Kabushiki Kaisha
• Nissan Chemical Industries, Ltd.
• Nissan Motor Co., Ltd.
• Nisshin Oillio Group, Ltd.
• Nisshin Seifun Group Inc.
• Nisshinbo Industries, Inc.
• Nissho Iwai Corporation
• Nitto Boseki Co., Ltd.
• Nomura Holdings, Inc.
• NSK Ltd.
• NTN Corporation
• NTT DATA Corporation
• NTT DoCoMo, Inc.
• Obayashi Corporation
• Odakyu Electric Railway Co., Ltd.
• Oji Paper Co., Ltd.
• Oki Electric Industry Company, Limited
• Okuma Corporation
• Olympus Optical Co., Ltd.
• Osaka Gas Co., Ltd.
• Pioneer Corporation
• Resona Holdings, Inc.
• Ricoh Company, Ltd.
• Sankyo Co., Ltd.
• SANYO Electric Co., Ltd.
• Sapporo Breweries Limited
• Secom Co., Ltd.
• Sekisui House, Ltd.
• Seven-Eleven Japan Co., Ltd.
• Sharp Corporation
• Shimizu Corporation
• Shin-Etsu Chemical Co., Ltd.
• Shionogi & Co., Ltd.
• Shiseido Company, Limited
• The Shizuoka Bank, Ltd.
• Showa Denko K.K.
• Showa Shell Sekiyu K.K.
• Sompo Japan Insurance, Inc.
• Sony Corporation
• Sumitomo Chemical Company, Limited
• Sumitomo Corporation
• Sumitomo Electric Industries, Ltd.
• Sumitomo Heavy Industries, Ltd.
• Sumitomo Metal Industries, Ltd.
• Sumitomo Metal Mining Co., Ltd.
• Sumitomo Mitsui Financial Group Inc.
• Sumitomo Osaka Cement Co., Ltd.
• Sumitomo Realty & Development Co., Ltd.
• The Sumitomo Trust and Banking Company, Limited
• Suzuki Motor Corporation
• Taiheiyo Cement Corporation
• Taisei Corporation
• Takara Holdings Inc.
• Takashimaya Company, Limited
• Takeda Chemical Industries, Ltd.
• TDK Corporation
• Teijin Limited
• Teikoku Oil Co., Ltd.
• Terumo Corporation
• TOA CORPORATION
• Toagosei Co., Ltd.
• Tobu Railway Co., Ltd.
• Toei Co., Ltd.
• Toho Zinc Co., Ltd.
• Tokai Carbon Co., Ltd.
• TOKYO DOME CORPORATION
• The Tokyo Electric Power Company, Incorporated
• Tokyo Electron Limited
• Tokyo Gas Co., Ltd.
• Tokyu Corporation
• Tokyu Department Store Co., Ltd.
• TOMEN Corporation
• Toppan Printing Co., Ltd.
• TOPY Industries, Limited
• Toray Industries, Inc.
• Toshiba Corporation
• Tosoh Corporation
• TOTO LTD.
• Toyo Seikan Kaisha, Ltd.
• Toyobo Co., Ltd.
• Toyota Motor Corporation
• Trend Micro Incorporated
• Ube Industries, Ltd.
• UFJ Holdings, Inc.
• UNITIKA Ltd.
• West Japan Railway Company
• Yamaha Corporation
• Yamanouchi Pharmaceutical Co., Ltd.
• Yamato Transport Co., Ltd.
• Yokogawa Electric Corporation
• The Yokohama Rubber Co., Ltd.
• Yuasa Corporation