Disproportionality may be due to the allocation of a minimum number of seats to each constituent state. Mexico uses the criterion of population for its single-member constituencies. The borders separating the 300 constituencies are drawn after dividing the country’s population by the number of constituencies, taking into account the most recent census. Each state shall have at least two representatives elected within the constituencies. The United States uses population for the House of Representative constituencies, the number of seats depends of the share of the aggregate population; each state will have at least one seat.