In 1925, Japan's Mining Office referred to coal reserves in the empire of 8,000 million tonnes, or 2,933 million tonnes (Kyūshū, Miiki and Mitsui deposits), 2,675 or 3,471 million tonnes (Hokkaidō, ones 1,113,600 million from Yubari mine), 1,362 million tonnes (Karafuto, in Kawakami deposits), 614 million tonnes (Honshū), 385 million tonnes (Formosa, in the Kirun area), 81 million tonnes (Korea). Extraction in Japan during 1912 was 20,000,000 tonnes, in 1932 in 30,000,000 tonnes and grew in 1941 to 55,500,000 tonnes and was divided between the following sources, in tonnes: Korea (5,000,000), Formosa (2,500,000) and Karafuto (2,500,000) and additional imports 4,000,000 tonnes from China and Indochina.