The most concentrated linguistic minority in the Czech Republic are ethnic Poles, historically the plurality, today constituting about 10% of the population of Karviná and Frýdek-Místek districts. Poles have the right to use their language in official dealings; the public media (Czech TV and Czech Radio) regularly broadcast in Polish; and there are many Polish primary and secondary schools in the area. The Polish minority has been decreasing substantially since World War II as education in Polish was difficult to obtain, while Czech authorities did not permit bilingual signs to maintain Polish awareness among the population.