Organizers revealed Shanghai expects to lose at least US$125 million by hosting the World Expo in 2010, but the estimate did not factor in the US$2.25 billion investment required for construction and the cost of moving nearly 20,000 families from the expo site into new housing. Organizers said the city would "do its best" to avoid overrunning the budget, but officials played down concerns, claiming the event will boost overall economic growth even if it did return a loss. Shanghai will turn to the central government to make up any shortfall. The metropolis is hoping 70 million people will visit the May to October 2010 expo, including 3.5 million from overseas. The German city of Hanover, which hosted the 2000 World Expo, lost US$1 billion when visitor numbers fell 22 million short of the projected 40 million.