Network Rail Limited is the owner (via its subsidiary Network Rail Infrastructure Limited, which was known as Railtrack plc before 2002) and infrastructure manager of most of the railway network in Great Britain. Network Rail is an "arm's length" public body of the Department for Transport with no shareholders, which reinvests its income in the railways. To cope with fast-increasing passenger numbers, (as of 2021) Network Rail has been undertaking a £38 billion programme of upgrades to the network, including Crossrail, electrification of lines and upgrading Thameslink.