A worker unties a stack of iron pipes after they are unloaded from a train wagon at a yard, in the western Indian city of Ahmedabad March 14, 2012. India's railway network is one of the world's largest, but years of low investment and populist policies have crimped growth and hindered private investment in a sector seen as crucial to the country's economic expansion. REUTERS/Amit Dave (INDIA - Tags: BUSINESS EMPLOYMENT TRANSPORT)