The nominal GDP of the city state Berlin totaled €90.1 (~$117) billion. Berlin’s economy is dominated by the service sector, with around 80% of all companies doing business in services. Fast-growing economic sectors in Berlin include communications, life sciences, and transportation particularly services that use information and communication technologies, as well as media and music, advertising and design, biotechnology, environmental services, and medical engineering. The Science and Business Park of Berlin-Adlershof is among the 15 largest technology parks worldwide. Research and development have high economic significance for the city, and the Berlin-Brandenburg region ranks among the top-three innovative regions in the EU. Many German and international companies have business or service centers in the city. For years Berlin is recognized as a centre of business startup in Europe. Among the 20 largest employers in Berlin are the Deutsche Bahn, the hospital provider, Charité, the local public transport provider, BVG, and the service provider, Dussmann and the Piepenbrock Group. Daimler manufactures cars, and BMW builds motorcycles in Berlin. Bayer Health Care and Berlin Chemie are major pharmaceutical companies headquartered in the city. The second largest German airline Air Berlin is also headquartered in Berlin. Siemens, a Fortune Global 500 company and one of the 30 German DAX companies, is headquartered in Berlin. The national railway operator, Deutsche Bahn, has its headquarters in Berlin as well. Berlin has a cluster of rail technology companies and is headquarter or site to Bombardier Transportation, Siemens Mobility, Stadler Rail and Thales Transportation.