Postal data – retention period unknown Information written on the outside of a postal item (such as a letter or parcel), online tracking of postal items, records of special postal items (such as records of registered, recorded or special delivery postal items), records of parcel consignment, delivery and collection. Banking data – seven years The Economist reported that UK banks are required to retain data on all financial transactions for seven years though this has not been verified.[citation needed] It is not clear whether data on credit card transactions is also retained for seven years. Vehicle movement data – two years Documents leaked from the Association of Chief Police Officers (ACPO) have revealed that the UK is planning to collect data from a nationwide network of automatic numberplate recognition cameras and store the data for two years in a controversial new centre being built at Hendon.[25] This data could then be linked to other data held by the government and watchlists from the police and security services.[26]