sentences:  The airport employs approximately 19,000 people.Manchester is served by four stations in the city centre; Manchester Piccadilly (18.5 million passengers), Manchester Victoria (9.8 million passengers), Manchester Oxford Road (8.3 million passengers) and Deansgate (0.35 million passengers), which form the Manchester station group with a combined passenger usage of 37 million passengers in 2011-12.Manchester will be at the heart of the £560 million Northern Hub development, which will see all four Manchester stations connected, increased electrification of networks, increased frequencies and reduced journey times between Northern cities.