Annex B
MAIN DATA SOURCES USED IN THIS SUBMISSION
INTERNATIONAL PASSENGER
SURVEY
1. This is a sample survey of passengers
arriving at, and departing from, the main United Kingdom air and
sea ports and the Channel Tunnel. Of those sampled, approximately
1% were migrant interviews in years up to 2007, which amounted
to around 3,000 interviews with migrants entering the country
and 800 with those departing. From 2007, the number of interviews
with departing migrants will be boosted to a comparable level
to those on entry.
2. The IPS sample is stratified to ensure
that it is representative by mode of travel (air, sea or tunnel),
route and time of day. Interviews are conducted throughout the
year. The information collected by the survey is weighted using
total passenger movements (eg from the Civil Aviation Authority)
to produce national estimates of migration. This is explained
in more detail in the annual international migration statistics
volume, http://www.statistics.gov.uk/downloads/theme_population/MN_no32.pdf
3. In terms of measuring migration, the
IPS has three main limitations:
— it does not cover all types of migration
(eg land routes between the UK and the Irish Republic, most asylum
seekers and some dependants of asylum seekers);
— as a sample survey, the estimates
are subject to a degree of uncertainty;
— migration estimates are based on
respondents' intentions, which may or may not accord with their
final actions. Adjustments are required to account for those who
change their intention, known as "switchers".
LABOUR FORCE
SURVEY (LFS)
4. The Labour Force Survey (LFS) is a quarterly
household survey run by ONS, representative of the household population
of the UK. The LFS collects a wide range of variables including
nationality and country of birth. The data can be used as an indicator
of the non-British or foreign born migrant numbers in the UK.
The population covered is all people resident in private households.
The LFS excludes most communal establishments although it does
cover most staff resident in National Health Service accommodation.
Students in halls of residence are covered by proxy through their
parents and thus foreign students living in halls of residence
are not likely to be covered—though those living in private
households will be. People who have not lived in the UK for six
months are excluded.
5. The sample includes households in multi-occupied
dwellings, although there is evidence that response rates for
multi-occupied dwellings are lower than for single household dwellings.
The sample is, however, weighted to take account of response rates
by age, sex and region and this goes some way to correcting for
differences in response.
NATIONAL INSURANCE
NUMBER (NINO)
ALLOCATIONS
6. National Insurance Numbers are issued
to individuals over the age of 16 and are used to record a person's
national insurance contributions and social security benefit claims.
New numbers are issued to migrants including:
— All non-UK born nationals aged 16
or over working, planning to work or claim benefits legally in
the UK, regardless of how long individuals intend to stay.
— Dependents of NINo applicants, unless
they work or claim benefits.
— Individuals from overseas not working,
planning to work, or claim benefits—for example, this will
include many students.
— Migrants who are not of working age
if not claiming benefits.
— Those with an existing national insurance
number, for example returning UK nationals.
7. Migrant statistics are based on HMRC
data, held on the NIRS computer system, on NINos allocated to
overseas nationals entering the UK; figures are available back
to 2000-01. The statistics show the number of people registering
for a NINo in order to work (including the self-employed and students
working part-time) or to claim benefits and tax credits. They
do not include other people who come to the UK and—being
flow data—they do not show the number of foreign nationals
working or claiming benefit at a given point in time nor do they
distinguish between long term and short term migration. They do
make a valuable contribution to the overall picture on immigration.
8. Data are tabulated by year of arrival
and registration, continent/country of origin, region of residence,
gender, age band, and subsequent benefit claims. A key strength
of this administrative source is that data are held at individual
level with 100% coverage and are particularly valuable as a local
area indicator (data are published at Parliamentary Constituency
and Local Authority District level), and for longitudinal analysis.
9. The statistics are derived as a byproduct
of an administrative system not designed primarily for statistical
purposes; meaning for example that statistics do not distinguish
between short-term and long-term migration and hence do not match
the UN definition of migration.
THE WORKER
REGISTRATION SCHEME
(WRS)
10. Following expansion of the European
Union on 1st May 2004, the Government put in place transitional
measures to regulate access to the labour market and to restrict
access to benefits for nationals from new member states. Nationals
of the A8 countries who wish to take up employment in the UK for
a period of at least a month are generally required to register
with the WRS. The statistics in this publication are only of those
who have registered with the Home Office to work as employees
in the UK. Workers who are self-employed do not need to register
and are therefore not included in these figures; there may also
be other workers from the accession countries who for one reason
or another do not register and are thus also not included in these
figures. Applicants must register more than once if they are employed
by more than one employer. They must also re-register if they
change employer. Each application to the WRS therefore represents
one job, not one applicant.
11. The population covered on the WRS includes:
— Long-term international migrants
from A8 countries working as employees in the UK.
— Visitors and short term migrants
from A8 countries, staying for over a month, and intending to
work as employees in the UK.
— Dependents of WRS applicants. It
is likely that there is some double counting as dependents may
also be registered in their own right on the WRS.
— Migrants from A8 countries who are
self employed.
— A8 migrants staying for less than
a month.
— A8 migrants who migrate or visit
the UK for reasons other than work, for example including potentially
many students.
— Migrants from non-A8 countries.
12. The data are based on the applicant's
place of work rather than usual residence. Although residence
is also collected, Home Office research indicates that workplace
is more accurate on the WRS. The figures produced are by date
of application rather than date of entry into the UK. Most figures
in the Accession Monitoring Report are based on the date the application
form was completed.
13. WRS operates as a transitional arrangement
following EU expansion in May 2004 so can not offer a permanent
alternative or supplementary count. Data will not be available
from the WRS after 2009, nor is it being collected from January
2007 for nationals from the latest accession countries (Bulgaria
and Romania).
4 October 2007
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