The growth of Pittsburgh and its economy
was caused by the extensive trade in steel through the 1970s. Pittsburgh has
since adapted to the collapse of the region's steel industry. The primary
industries have shifted more to high technology, such as robotics, health care,
nuclear engineering, tourism, biomedical technology, finance, and services. As
of 2007, the total annual payroll of the region's technology industries, when
taken in aggregate, exceeded $10.8 billion, and as of 2010, there were 1,600
technology companies. Reflecting the citywide shift from industry to
technology, some former
