ONS Population Estimate Revisions

ONS has made revisions to their mid-year population estimates for England and Wales from mid-2012 to mid-2016. For the vast majority of local authorities, these revisions have been very minor. However, for a small handful of authorities, the change is large enough to affect how decisions are made in the local area.

In order to take into account these changes, we have made revisions to all of the indicators in Local Insight which are derived from the ONS population estimates. This includes not just the population estimate figures themselves, but also any figure which uses the population estimates to calculate a rate e.g. Unemployment claimant count uses the working-age population from the ONS population estimates, combined with DWP data on counts of Universal Credit and Jobseekers Allowance claimants to calculate the unemployment rate. In total 196 of the 924 Indicators on Local Insight have been affected by the population revisions.

Click here for a full list of affected indicators.

Please note: there may be discrepancies between Local Authority and small area data

The revisions to the ONS population estimates have been released at Local Authority (LA) level only, with the population estimates for neighbourhood geographies (LSOAs, MSOAs, Output Areas etc.) still based on the unrevised estimates.

Revisions to the neighbourhood geographies are due to be published in Autumn 2018, but in the meantime, there will be inconsistencies between LA and MSOA/LSOA/Output Area data for the 196 indicators which are derived from ONS population estimates.

For example, the total population for all of the LSOAs in an LA will no longer add up to the total population of that LA as the LSOA data will be based on unrevised estimates and the LA data will be based on revised estimates. These inconsistencies could also potentially occur depending on whether your custom areas are built up from LSOA geographies or LA geographies.

Minimising the risk of misinterpretation

We have included health warnings for each of the affected indicators in the About the indicator pop-up and in the Introduction page of the report. These health warnings will remain in the metadata until the small area data is revised to be consistent with the LA data in Autumn 2018.

Out of 348 local authorities, only 28 have had their population estimate for mid-2016 revised by 1% or more; a minority of areas have seen notable changes to their overall population estimates. The population in one LA (Wandsworth) has been revised upwards by more than 5,000 people, while four LAs have been revised downwards by more than 5,000 people (Cambridge, Haringey, Oxford and Westminster).

Downward revisions have mostly resulted from higher emigration estimates for areas containing international students and lower immigration estimates for Inner London. For more details see ONS’ Revised population estimates for England and Wales: mid-2012 to mid-2016

Get in touch

If you require any further clarification, please don’t hesitate to get in touch with us at support@ocsi.co.uk or give us a call on 01273 810270.