Most French departments are assigned a two-digit number, the "Official Geographical Code", allocated by the "Institut national de la statistique et des études économiques". Overseas departments have a three-digit number. The number is used, for example, in the postal code, and was until recently used for all vehicle registration plates. Residents commonly use the numbers to refer to their own department or a neighbouring one, for example, inhabitants of Loiret may refer to their department as "the 45". More distant departments are generally referred to by their names, as few people know the numbers of all the departments.