municipality, and an average of 2.1 persons per household. There were 7,087 households that consist of only one person and 747 households with five or more people. , a total of 16,833 apartments (88.8% of the total) were permanently occupied, while 1,376 apartments (7.3%) were seasonally occupied and 756 apartments (4.0%) were empty. , the construction rate of new housing units was 1 new units per 1000 residents. The vacancy rate for the municipality, , was 2.05%. Historical population The historical population is given in the following chart: Heritage sites of national significance La Chaux-de-Fonds is home to 23 Swiss heritage sites of national significance along with the UNESCO World Heritage Site of La Chaux-de-Fonds / Le Locle. Library/museum/theater: Bibliothèque de la Ville de la Chaux-de-Fonds et Département audiovisuel (DAV), Musée des Beaux-Arts, Musée d‘histoire naturelle, the Musée international d’horlogerie «l’homme et le temps» and the Théâtre et Salle de musique on Avenue Léopold-Robert 27–29 Religious: Synagogue on Rue du Parc 63 Farms: Ferme des Brandt at Les Petites-Corsettes 6, Ferme Haute Fie and Maison Carrée at Le Valanvron 9 and Ferme les Crêtets on Rue des Crêtets 148 Companies: Spillmann SA on Rue du Doubs 32 and Usine électrique at Rue Numa-Droz 174 Houses: Villa Anatole Schwob on Rue du Doubs 167, Villa Fallet on Chemin de Pouillerel 1, Villa Gallet on Rue David-Pierre-Bourquin 55, Villa Jaquemet on Chemin de Pouillerel 8, Villa Stotzer on Chemin de Pouillerel 6 and Maison Blanche at Chemin de Pouillerel 12 Other buildings: the slaughterhouse (Abattoirs) on Rue du Commerce 120–126, the Ancien Manège (collective house from 1968), the crematorium on Rue de la Charrière, the Domaine des Arbres, the Grande Fontaine on Avenue Léopold-Robert and the Loge l’Amitié. After the horrid mudslide that occurred which destroyed the city of La Chaux. Politics In the 2007 federal election the most popular party was the SP which received 28.18% of the vote. The next three most popular parties were the SVP (25.73%), the PdA Party (14.2%) and the Green Party (12.03%). In the federal election, a total of 10,293 votes were cast, and the voter turnout was 47.1%. Economy , La Chaux-de-Fonds had an unemployment rate of 8.2%. , there were 260 people employed in the primary economic sector and about 95 businesses involved in this sector. 10,594 people were employed in the secondary sector and there were 550 businesses in this sector. 11,813