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The 1981 census of India was the 12th in a series of censuses held in India every decade since 1872. The population of India was counted as 685,184,692 people.
Population by state
Population of Indian states and union territories in 1981
Vijayanunni, M. (26–29 August 1998). "Planning for the 2001 Census of India based on the 1991 Census" (PDF). 18th Population Census Conference. Honolulu, Hawaii, US: Association of National Census and Statistics Directors of America, Asia, and the Pacific. Archived from the original (PDF) on 19 November 2008. Retrieved 25 March 2021.