ONS Release 2.4


Earlier today, ONS published the following five tables:

  • AP1101EW Sex by five-year age group (non-UK born short-term residents)
  • AP1102EW Sex by single year of age (non-UK born short-term residents)
  •  AP1201EW Country of birth (non-UK born short-term residents)
  • AP1202EW Passports held (detailed) (non-UK born short-term residents)
  • AP1601EW Economic activity (non-UK born short-term residents)

A further four Quick Statistics tables were also released, detailing Passports held, Country of birth, National Identity, and Approximate social grade.

These tables can be downloaded from the ONS website and will be available in SASPAC shortly.

Beyond 2011 Consultation


A Beyond 2011 Consultation was issued on Monday 18 March 2013 regarding user requirements for future population and socio-demographic information.

The Beyond 2011 programme is an ongoing programme within National Records of Scotland (NRS) to research suitable methods for producing population and socio-demographic information.

The questionnaire for user requirements can be completed on the NRS website or via www.surveymonkey.com. It can be responded to until Monday 10 June 2013.

More information on the Beyond 2011 programme and Stakeholder engagement sessions can be found on the NRS website or by contacting the Beyond2011 team.

Creating Improved Census Ward Population Estimates


ONS’ GSS policy of best-fitting 2011 Census estimates (and other national statistics) from output areas has been causing issues for some local authorities that have seen ward boundary changes since 2003. SASPAC has received considerable interest from users on this particular issue as well as discussion on the StatsUserNet and Knowledge Hub forums.

The Issue

All 2011 Census ward estimates have been created using a method of best-fitting from the population weighted centroids of the underlying 2011 Census Output Area (OA). The population weighted centroid is a single point within the OA that represent the median location of households. The whole population of this OA is then assigned to the ward in which it falls. This means that where OA boundaries no longer match ward boundaries (i.e. they have changed since 2003 when the 2001 Census OAs were produced on an exact-fit to wards) the population/household estimates may not reflect all households physically located within the ward boundary. Conversely households outside the ward boundary may be included.


2011 best-fit of OAs to Wards: OA4 is allocated to WARD 2 because OA4’s population weighted centroid falls within the WARD 2 boundary (Source: ONS, An overview of best-fitting: Building 2011 Census Estimates from Output Areas)

Creating improved estimates

This is leading many organisations to look out how they can create improved best-fit estimates using alternative methods of redistributing the OA population more accurately. A number of methods can be used such as:

  • using the proportion of each OA’s areal extent that falls within each ward (assumes the population is evenly distributed across the OA) or,
  • using Census day address lists (e.g. Royal Mail Postcode Address File or the Local Land and Property Gazetteers maintained by local authorities) to distribute the population. Tees Valley Unlimited have very helpfully documented their approach here.  

Another approach will be possible when the 2011 Census Unit Postcode Headcount data (Postcode estimates tables are currently expected in May (p35 of the 2011 Census Prospectus (.pdf)) are published. These will provide details of the number of males, females and occupied households for each Census day postcode and will provide a very accurate method of redistributing the population to ward boundaries.

How SASPAC can help?

Once you have created the improved OA population distributions, SASPAC’s rezoning tool can then be used to easily recreate all the Census tables for these more accurate ward household or population distributions. For more information in how to rezone in SASPAC see Module 4 of our training manual.

Census estimates for other areas such as Parishes have also been best-fitted from whole OAs. This re-estimation method can be applied to any zones where best-fitted figures are insufficiently precise.

But remember…

Creating your own local ward estimates will produce alternative figures to those officially produced by ONS and should be documented and correctly labelled as such to avoid any confusion. Also, the best-fit methodology will be applied to create other ONS datasets, so care should be taken to use denominators created using the best-fit method.

Some useful resources:

ONS page on exact and best-fit estimates

ONS overview of the best-fitting methodology

Download median population weighted centroids for output areas, super output areas and workplace zones in shp and mid/mif format.

ONS National Postcode Directory

ONS 2001/2011 Census geography lookups products

Scottish Census Release


Today NRS released the latest results from the 2011 Census. Release 1B includes:

  • usually resident census population estimates (rounded to the nearest 100) for Scotland, by five-year age bands and sex;
  • usually resident census population estimates (rounded to the nearest 100) for each council area, by five-year age bands and sex;
  • estimates of number of households (rounded to the nearest 10) for Scotland and each council area
  • Additional Quality Assurance, methods material and interactive data visualisations.

Individual tables in xls, csv and pdf formats are available to download from the NRS download page.


The next data release is scheduled for May and will include single year of age estimates for council areas. For more details on subsequent releases see the latest Census Output Prospectus available from here.

Early 2013/14 SASPAC payments


With the end of the financial year nearly upon us, your organisation may wish to take advantage of any underspend (if you’re lucky to have any?!) and use 2012/13 budgets to finance next year’s SASPAC Support fee or purchase. If so, please contact the helpdesk with a purchase order number and invoice contact details as soon as possible.

With the flow of 2011 Census beginning to pick up pace (latest ONS & NRS plans), make sure your organisation is well prepared to take advantage of these datasets with access to the essential Census software and support services provided by the SASPAC team.

Scotland 2011 Census Update


Yesterday, NRS published an update to the 2011 Census Outputs Prospectus for Scotland. The key points are:


  • Local Authority level five-year age band population estimates (release 1B) are scheduled for release on 21 March, with single year data (release 1C) following in May.
  • Key & Quick Statistics tables (release 2) will begin in Summer 2013, Local Characteristics (release 3) in Autumn 2013, and Winter 2013 (release 4) will contain Detailed Characteristics tables.
  • Table layouts for Key and Quick Statistics are now available on the NRS website (.xls)
  • NRS are keen to hear from users if they should follow ONS/NISRA and change the order of Releases 3 and 4

All the Census outputs relating to releases 2, 3 and 4 will be made available through SASPAC.