Since reunification on 3 October 1990, Berlin has been one of the three city states in Germany among the present 16 states of Germany. The House of Representatives (''Abgeordnetenhaus'') functions as the city and state parliament, which has 141 seats. Berlin's executive body is the Senate of Berlin (''Senat von Berlin''). The Senate consists of the Governing Mayor (''Regierender Bürgermeister''), and up to ten senators holding ministerial positions, two of them holding the title of "Mayor" (''Bürgermeister'') as deputy to the Governing Mayor. The total annual state budget of Berlin in 2015 exceeded €24.5 ($30.0) billion including a budget surplus of €205 ($240) million. The state owns extensive assets, including administrative and government buildings, real estate companies, as well as stakes in the Olympic Stadium, swimming pools, housing companies, and numerous public enterprises and subsidiary companies.