 The communities of common regime have the ability to add a surcharge to the so-called "ceded taxes"—taxes set at the central level, but collected locally—and they can lower or raise personal income taxes up to a limit.The Basque Country and Navarre were granted an exception in the fiscal and financial system through the first additional disposition of the constitution that recognizes their historical "charters" —hence they are known as "communities of chartered regime" or "foral regime".Through their "chartered regime", these communities are allowed to levy and collect all so-called "contracted taxes", including income tax and corporate tax, and they have much more flexibility to lower or raise them.