The division of England and Wales into Output Areas was completed on 23 January 2003. These are the new small area building bricks for the release of 2001 Census results and for use more widely in Neighbourhood Statistics.
There are some 175,500 Output Areas in England and Wales. They were created around a target population of 125 resident households, and 37.5% lie between 120 and 129 households, whilst 79.5% lie between 110 and 139 households. Some 5% lie between 40 households - the confidentiality threshold - and 99 households, and many of these are a single parish (or community in Wales).
The Output Areas nest within ward and parish (community in Wales) boundaries legally in place at the end of 2002, as explained in a note issued in Census News in early November 2002. Draft boundaries were used in a few local authorities where final versions did not become available. Information on the operative dates for the district, ward and parish boundaries in each local authority is listed HERE (as an Excel file), together with the number of Output Areas in each authority.
The authorities are arranged on the spreadsheet as viewed initially in the standard order for the presentation of statistics: Greater London; Metropolitan areas; Unitary Authorities in England(in Government Office Region order); Unitary Authorities in Wales (in geographical order); Countries in England (in alphabetical order). Where no 'operative date' is shown for an authority, boundaries used in the creation of output areas are as at Census Day (29.04.01).
The Output Area information is now going through a final QA, and preparations for the release of boundary files and look up tables are under way. Free-standing versions will be available in the second half of February under the 'free at the point of use' terms of Census Access, and interest and orders should be registered with Census Customer Services. Later, boundaries will be released with statistics on the Neighbourhood Statistics Website and on CDs. More details will be given in Census News before each release.
The Census Output Prospectus contains more details about the creation of Output areas with some illustrative maps.
Output Areas
The geographical framework for Census/NeSS
postcode based building bricks, nesting within up to date '2003' ward and parish boundaries
created in an automatic process, using 1 metre co-ordinate referenced Census records and other boundary and map information, in which
- polygons are created around every address
- these are grouped to form unit postcode polygons
- the postcodes are zoned into Output Areas using objective and systematic statistical criteria
the process delivers
- consistently sized areas
- boundaries for GIS and electronic media
- look up tables for postcode links to non-Census data
- population weighted centroids and area measurements
Census News
