The mid-year population estimates for 2002 (MYEs) were published on 26 September 2003. These were based on revised MYEs for 2001.
Interim Revised National Estimates 1992 to 2000
There is a need for national estimates for time series and other uses that form a series that has no break. Some users need such a series very quickly.
The interim revised national estimates will be produced using a simple methodology that can be quickly implemented. This methodology is likely to draw upon existing estimates for 1992 to 2000, and allocate the difference between the original 2001 estimates and revised 2001 estimates, allocating this across the decade. The precise methodology will require some research in order for a consistent series to be delivered. Details of the methodology used will be published alongside the interim estimates.
Revised National and Sub-national Estimates 1992 to 2000
These will provide the definitive estimates of population for the 1990s. Estimates prior to 1992 will not be changed, and existing estimates for this period should be regarded as definitive.
Production of the revised estimates will require significant time for research as well as for production and quality assurance. In order for the best possible estimates to be derived, it was not possible to commit to a timetable earlier than spring 2004.
We took this time to address a number of issues that have only come to light after publication of the existing series. Whilst the overall methodology for revisions was sound and provided estimates fit for most purposes, it did cause issues for certain limited uses, for example in constructing participation rates in education by children aged 5 to 19. Therefore, modifications to this methodology will need to be carefully researched.
Since the revised MYEs were published in February 2003, revised international migration estimates for 1992 to 2000 have become available, these were published in June 2003. In spring 2004 we undertook the complicated task of examining the possibility of incorporating these revised migration estimates into the revisions for 1992 to 2000.
Marital Status Estimates, Population Estimates for Primary Care Trusts, and Quarterly Population Estimates
The revisions to 2001 MYEs will have a knock-on impact on 2001 marital status MYEs so we will be revising 2001 marital status MYEs.
In order to complete the program of research that was required to produce revised 2001 MYEs it has been necessary to put on hold the research required to produce population estimates on Primary Care Trust boundaries. Similarly, work on the assessment of accuracy for marital status MYEs and consequent production of revised 1982 to 2000 marital status MYEs has also been delayed. We publisheed the results for marital status in early 2004, and spring 2004 for MYEs on Primary Care Trusts boundaries.
There are more lessons to be learned from the 2001 Census and it will continue to provide valuable additional insights for population estimates for some time. We will be taking on board these lessons and insights in our continuous research program. We will also be acting upon the recommendations made in the report: 'A Demographic Statistics Service for the 21st Century'. It will take time to implement these recommendations, but as we do so this will mean higher quality estimates, and estimates that can be used for a wider range of uses. We will consult with users as the research programme develops. As improved methods and sources are put in place there may be a need to revise MYEs for earlier years.
Part of the future work programme will be to develop, in consultation with users, a revisions policy for population estimates.
The Office for National Statistics (ONS), in conjunction with the Home Office, has also recently published (2 September 2003) a National Statistics Quality Review on International Migration. This review will have a number of impacts that are aimed at improving the quality of migration statistics in the future, with consequent improvements for the population estimates that use these migration estimates. Here is a link to the NSQR report for international migration. ONS has published an action plan for future research aimed at implementing the recommendations of the NSQR on international migration