Information on the nationality of foreign nationals held in prison establishments in England and Wales is given in the population in custody detailed table 2.14 of Offender Management Caseload Statistics Quarterly Brief October to December 2005, available at the following web address:
http://www.homeoffice.gov.uk/rds/omcs.html
These figures have been drawn from administrative IT systems. Although care is taken when processing and analysing the returns, the detail collected is subject to the inaccuracies inherent in any large scale recording system, and so is not necessarily accurate to the last whole number.
[holding answer 12 July 2006]: Information on discharges is not available in the detail the hon. Gentleman requests.