British Rail was privatised between 1994 and 1997, involving the transfer to a series of private-sector operators of responsibility for the provision of services under contract. In all, more than 100 companies took over from British Rail. In 2001 the track operator Railtrack went bankrupt; it was reconstituted and renamed as Network Rail, a private company with no legal owner but effectively government-controlled via its constitution and financing. The United Kingdom government continues to invest in the railways, financing, for example, the acquisition of some InterCity rolling stock.