The Chamber of Deputies, officially the Chamber of Deputies of the Parliament of the Czech Republic, is the lower house of the Parliament of the Czech Republic. The chamber has 200 seats and deputies are elected for four-year terms using the party-list proportional representation system with the Imperiali and Hagenbach-Bischoff quotas. Since 2002, there have been 14 constituencies, matching the Czech regions, with district size varying from 8 to 26 representatives. A Cabinet is answerable to the Chamber of Deputies and the Prime Minister stays in office only as long as they retain the support of a majority of its members. The quorum is set by law to one third (67) of elected deputies. Any changes to the constitutional laws must be approved by at least 60 percent of the Chamber of Deputies. The seat of the Chamber of Deputies is the Thun Palace in Malá Strana, Prague.