Sub-national entities are often dominated by one party due to the area's demographic being on one end of the spectrum. For example, the current elected government of the District of Columbia has been governed by Democrats since its creation in the 1970s, Bavaria by the Christian Social Union since 1957, Madeira by the Social Democrats since 1976, and Alberta by Progressive Conservatives from 1971 to 2015. On the other hand, where the dominant party rules nationally on a genuinely democratic basis, the opposition may be strong in one or more subnational areas, possibly even constituting a dominant party locally; an example is South Africa, where although the African National Congress is dominant at the national level, the opposition Democratic Alliance is strong to dominant in the Province of Western Cape.