Figures for areas which overlap those in the standard geographical hierarchy are generally the sum of the counts for the best fit of standard areas, rather than exact counts.
This is to remove any risk that personal Census information might be inadvertently disclosed by differencing of standard sets of counts for overlapping areas. Best fitted figures are limited to those available from the component standard areas.
Most commonly, Output Areas (OAs) are built to best fit wards and other administrative areas where boundaries have been revised after 31 December 2002 (the reference date for the boundaries used to present most 2001 Census results). Where an OA is not wholly within a new area, it is included or excluded on the basis of the location of the majority of its population at Census time placed by their coordinate references in relation to the digital boundary for the new area.
Every 2001 Census record has a National Grid coordinate reference (with a resolution of 1 metre) which allows the records to be sorted by computer processes into areas defined by digital boundaries.
Census Area Statistics (CAS)
The standard set of summary figures, with more detailed tables inter-relating characteristics, available for a range of areas from the most local to the national level. They include all topics covered by the 2001 Census, and are designed to facilitate comparisons.
The CAS comprise of:
Key Statistics - summary figures, also presented as percentages for larger areas.
CAS tables - cross tabulations inter-relating two or more characteristics.
univariate tables - counts giving a more detailed breakdown of a single characteristic.
theme tables - cross tabulations relating various characteristics to standard categories for a particular group in the population.
Equivalents of all figures in the CAS may be found in the more detailed Standard Tables, to facilitate comparison, although they may be broken down into more categories.
County/local authority district
The upper and lower tiers of local government in parts of England.
The 34 'shire' counties, together with a lower tier of 239 local authority districts, administer local government outside Greater London, the metropolitan counties, and Unitary Authorities in England.
Counties are long established, and formerly covered the whole of England and Wales, but various restructuring changed boundaries, introduced new counties, and abolished others.
Comma Separated Variable (CSV) is an industry standard file format in which values are separated by a comma, with values in predetermined positions. Census results are available in two versions of the format.
The results available on the Neighbourhood Statistics website can be downloaded in the format which can be read by a number of spreadsheet packages. The results supplied direct by Census Customer Services are in the format designed to load into database systems, and are not designed to be used in spreadsheet packages. These provide data in DATA files, descriptions of the row and column labels in DESC files, and table numbering, title information, and footnotes in META files - a structure agreed with large volume users.
DBF is an industry standard file format. A DBF file contains a header record and data records. The structure of the file is defined in the header record, and this also contains any other information related to the file. Data records follow the header.
Digital / raster / vector boundary
Boundaries in electronic form for reproduction and manipulation, largely replacing supply as paper copies.
A linear boundary is converted into a series of coordinate references of sufficient frequency, particularly where the boundary changes direction, to allow it to be reproduced at a required scale as a line joining the referenced points. Supplementary data relate the boundary to the area(s) which it defines, and facilitate the reproduction of a complex set of boundaries.
Digital boundaries in raster form allow reproduction, for example the maps of Census boundaries viewable on the Neighbourhood Statistics website, whilst boundaries in vector form available in these Census products allow manipulation and re-use through geographical information system (GIS) software.
Disclosure protection / confidentiality
Measures applied to all 2001 Census output in England and Wales to prevent the inadvertent disclosure of personal Census information about identified individuals.
England and Wales, England, Wales
England and Wales are two of the four parts of the United Kingdom, together with Scotland and Northern Ireland.
The Census Act 1920 authorises the Registrar General to conduct a Census in England and Wales, and reports for England and Wales are laid before Parliament. Results presented for England and Wales as a whole are usually also available for England as a whole, the nine Government Office Regions for England, and Wales as a whole.
Certain government responsibilities were devolved to the National Assembly for Wales in 1999 and bilingual Welsh/English reports have been produced from the 2001 Census to meet requirements of the devolved administration.
There is separate Census legislation for Scotland and for Northern Ireland and reports are made separately, although there is a substantial common core of standard and comparable 2001 Census results throughout the United Kingdom in the reports, Standard Tables, and Census Area Statistics (CAS).
Areas providing workloads and an organisational structure for the delivery, collection, and processing of the 2001 and earlier Censuses.
From the 1961 to the 1991 Census, Enumeration Districts (EDs) were the smallest area for which results were made available. They 'nested' within administrative areas, and were handled as units throughout processing. They were, however, primarily designed for operational rather than statistical purposes, and were redrawn for each Census. They were superseded for 2001 Census output purposes by Output Areas (OAs). OAs generally do not map onto EDs.
European electoral region
Returns a member to the European Parliament.
The twelve regions comprise the nine Government Office Regions of England, together with Wales, Scotland, and Northern Ireland.
A report with figures of the numbers, sex, and age of the resident populations at Census day (29 April 2001) for the United Kingdom, England and Wales, Government Office Regions in England, Wales, and each local authority in England and Wales, with a separate bilingual Welsh /English report for Wales.
Government Office Region
Regions set up in England in 1994 to coordinate the regional activities of a number of government departments, and which form the primary statistical subdivision of England.
Government Office Regions (GORs) succeeded the Standard Statistical Regions, previously used to report Census results, and differ in geographical definition.