Oil and Natural Gas Corporation Limited (ONGC) is a multinational oil and gas company headquartered in Dehradun, Uttarakhand, India. It is a Public Sector Undertaking (PSU) of the Government of India, under the administrative control of the Ministry of Petroleum and Natural Gas. It is India's largest oil and gas exploration and production company. It produces around 69% of India's crude oil (equivalent to around 30% of the country's total demand) and around 62% of its natural gas. On 31 March 2013, its market capitalisation was INR 2.6 trillion (US$48.98 billion), making it India's second largest publicly traded company. In a government survey for FY 2011-12, it was ranked as the largest profit making PSU in India. ONGC has been ranked 357th in the Fortune Global 500 list of the world's biggest corporations for the year 2012. It is ranked 22nd among the Top 250 Global Energy Companies by Platts. ONGC was founded on 14 August 1956 by Government of India, which currently holds a 68.94% equity stake. It is involved in exploring for and exploiting hydrocarbons in 26 sedimentary basins of India, and owns and operates over 11,000 kilometers of pipelines in the country. Its international subsidiary ONGC Videsh currently has projects in 15 countries. ONGC has discovered 6 of the 7 commercially producing Indian Basins, in the last 50 years, adding over 7.1 billion tonnes of In-place Oil & Gas volume of hydrocarbons in Indian basins. Against a global decline of production from matured fields, ONGC has maintained production from its brownfields like Mumbai High, with the help of aggressive investments in various IOR (Improved Oil Recovery) and EOR (Enhanced Oil Recovery) schemes. ONGC has many matured fields with a current recovery factor of 25-33%. Its Reserve Replacement Ratio for between 2005 and 2013, has been more than one. During FY 2012-13, ONGC had to share the highest ever under-recovery of INR 494.2 million (an increase of INR 49.6 million over the previous financial year) towards the under-recoveries of Oil Marketing Companies (IOC, BPCL and HPCL).