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Switzerland has four official languages: principally German (63.5% total population share, with foreign residents, in 2013); French (22.5%) in the west; and Italian (8.1%) in the south. The fourth official language, Romansh (0.5%), is a Romance language spoken locally in the southeastern trilingual canton of Graubünden, and is designated by Article 4 of the Federal Constitution as a national language along with German, French, and Italian, and in Article 70 as an official language if the authorities communicate with persons who speak Romansh. However, federal laws and other official acts do not need to be decreed in Romansh.

What is the principal official language in Switzerland?
German