Skip to main content

Migrant Workers: Chelmsford

Volume 468: debated on Monday 26 November 2007

To ask the Chancellor of the Exchequer what estimate he has made of the number of migrant workers there were in West Chelmsford constituency in each of the last five years. (166240)

The information requested falls within the responsibility of the National Statistician, who has been asked to reply.

Letter from Karen Dunnell, dated 26 November 2007:

As National Statistician, I have been asked to reply to your Parliamentary Question on migrant workers in West Chelmsford constituency. (166240)

The Office for National Statistics compiles statistics on employment for local areas from the annual Labour Force Survey (LFS) and the Annual Population Survey (APS) following International Labour Organisation definitions.

The data for analysing migrant workers comes from the Labour Force Survey (LFS). The National Statistics method for estimating the number of migrant workers employed in the UK is routinely based on the number of people at a given time who were born abroad, are of working age (16 - 64 for men, 16 - 59 for women), and in employment. This question has been answered on this basis. It means, for example, that some people who are UK nationals will be included in the total of “foreign born” and that people who are working but are above state pension age are not included.

When interpreting these figures, it is important to bear in mind that the annual LFS and APS is not designed to cover everyone who is present in the UK. The survey may undercount the numbers of people who were born overseas. The reasons are set out in the table footnote.

The annual LFS and APS estimates at this detailed level are only available consistent with population estimates published in February and March 2003 and are not comparable with the estimates published in the Labour Market Statistics First Release on 14 November 2007, which are based on latest population estimates.

The table attached, shows the numbers of working age in employment who were not born in the UK and were resident in West Chelmsford, for the twelve month periods ending in February for 2003 and 2004 from the annual LFS, and for the twelve month periods ending in March 2005, March 2006 and December 2006 from the APS (the January to December 2006 APS dataset is the most recent for which information on country of birth is currently available).

The table also shows the numbers of non-UK born persons in employment as percentages of all persons of working age in employment, in the area.

As these estimates are for a subset of the population in small geographical areas, they are based on small sample sizes, and are therefore subject to large margins of uncertainty. In this case, the sample sizes are not sufficient to give an accurate estimate of even the direction of the change over time.

Number of non-UK born persons of working age1 in employment in the West Chelmsford constituency

12 months ending

Employment level (thousand)

Non-UK born persons in employment as percentage of all in employment (percentage)

March 2003



March 2004



March 2005



March 2006



December 2006



1 Includes males aged 16 to 64 and females aged 16 to 59.


1. Estimates are subject to sampling variability.

2. It should also be noted that the country of birth question in the LFS gives an undercount because:

it excludes certain people who have not been resident in the UK for six months.

it excludes students in halls who do not have a UK resident parent.

it excludes people in most other types of communal establishments (e.g. hotels, boarding houses, hostels, mobile home sites, etc).

it is grossed to population estimates which exclude migrants staying for less than 12 months.

microdata are grossed to population estimates consistent with those published in spring 2003 which are significantly lower than the latest population estimates.


Annual Population survey