Vodafone Group is the world's largest mobile telecommunications company measured by revenues and the second largest measured by subscribers. It operates in over 30 countries and has partner networks in over 40 additional countries. Some key facts are that it is headquartered in London, was founded in 1984, and had revenues of $45.88 billion in 2011. It has acquired other operators to expand its operations, such as acquiring a 67% stake in Hutchison Essar in India in 2007.