What do you mean by constituency?
Under Article 82 of the Constitution, the Parliament by law enacts a Delimitation Act after every census. After coming into force commencement of the Act, the Central Government constitutes a Delimitation Commission. This Delimitation Commission demarcates the boundaries of the Parliamentary Constituencies as per provisions of the Delimitation Act. The present delimitation of constituencies is based on 1971 census figures. Population is the basis of allocation of parliamnetary constituencies of the Lok Sabha. As far as possible, every State gets representation in the Lok Sabha in proportion to its population as per census figures.