Coal India Limited is an Indian state-owned coal mining company headquartered in Kolkata, West Bengal, India. It was formed in 1975 by nationalizing coal mines. Coal India operates through 8 subsidiaries and mines coal in 8 states. It has a total of 471 mines of which 164 are open cast and 275 are underground. Coal India aims to produce and market coal efficiently while protecting the environment. It has over 90% market share in the Indian coal industry. In 2013-14, Coal India achieved a post-tax profit of Rs. 15,111.67 crores. It is involved in various CSR activities related to education, healthcare, infrastructure and disaster relief.