Most countries using multi-member constituencies provide for reallocation. For example, in Albania, the Central Electoral Commission reallocates the seats for each electoral zone based on the total number of citizens and the number of citizens for each region based on the National Civil Status Register. The proposal for reallocation has to be approved by the Assembly, no later than 6 months before the end of its mandate. In case of early elections there is no reallocation procedure. Austria determines the number of seats per constituency after every census. In Belgium the number of inhabitants in each electoral constituency is established every 10 years by a census or other means defined by law. The King publishes these results within six months. Within three months, he has to assign each constituency a number of seats proportional to its population. In Costa Rica the Supreme Electoral Tribunal reallocates the seats to the constituencies after each general population census. Spain provides for reallocation because of population changes. Switzerland provides for reallocation after each census. Turkey also reallocates the seats after each census. Reallocation takes place inter alia also in Chile, Costa Rica, Iceland, Latvia, Norway and Sweden.