The truth behind UK migration figures

Heathrow border control

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Ever wondered how many people are moving to, and leaving, the UK? If so, you're not the only one - the official figures are said by some experts to be based on not much more than guesswork.

Yes, despite few issues mattering more to politicians and the public than migration, the UK still does not have an accurate system for counting people in and out.

The e-borders scheme - which was meant to do this job - is still a work in progress, and despite government assurances to the contrary, there are some who fear it might stay that way.

Instead the government relies on the answers given by a sample of travellers who agree to be stopped and questioned by a team of social survey interviewers at Heathrow and other main air, sea and rail points of entry to the UK.

And despite the increasingly high hurdles to jump through to get a visa to come to the UK, it seems there is no way of knowing if someone is still in the country when it expires.

UK population

Crowd of shoppers
  • According to the 2011 census there are 53 million people in England; 3.1 million in Wales; and 1.8 million in Northern Ireland
  • The figure for Scotland - and the whole of the UK - will be announced in December
  • The population of England and Wales has risen by 3.7 million in a decade - the largest increase since records began
  • The growth was fuelled by increased life expectancy, a rise in fertility rates and immigration
  • The 2011 census could be the last - the government is looking into cheaper and more responsive alternatives

Keith Vaz, chairman of the influential home affairs committee says he finds it incredible that a supermarket loyalty scheme can collect and store details on the shopping habits of millions of people, yet a similar database can not be set up to record arrivals and departures.

Particularly when the coalition government sets such store by reducing "net migration" - the difference between the number of people entering and leaving the country.

So if Britain does not count everybody in as they arrive, and count them out again as they depart, where exactly do the net migration figures announced each quarter by the government come from?

The main source is the International Passenger Survey (IPS), which was designed in the early 1960s to find out how much foreign tourists were spending in the UK - something it is still used for today.

It works something like this: There are about 240 IPS officials stationed at major airports and ports around the country.

They pick out every 10th, 20th or 30th passenger streaming through arrivals or departures, depending on how busy they are that day, and ask if they wouldn't mind taking part in a short survey.

"There may be times when, owing to a particular flood of passengers, you just cannot keep an accurate count. Do not panic if this happens but keep counting as best you can," advises the Office for National Statistics training manual.

'Hopelessly inadequate'

The ONS takes the raw IPS data and adds information about asylum seekers and migration statistics from Northern Ireland, as well as figures for people who have entered the country on short-term visas and decided to ask to extend their stay, before arriving at a final immigration figure.

About 300,000 people are interviewed each year by IPS officials - about 0.2% of the 200 million who enter and leave the UK over the same period.

The IPS has been considerably beefed up in the past three years, after it came in for stinging criticism from senior figures, including Bank of England governor Mervyn King, who branded it "hopelessly inadequate".

The ONS admits the survey is still not perfect but points out that 800,000 people are sampled to find the 300,000 interviewees and it has cast its net wider than Heathrow, where most interviewers were based, to other airports around the country and ferry terminals at Dover and Portsmouth it says 95% of travellers now "have a chance" of being interviewed.

It also has the virtue of being long established and relatively cheap.

But it is entirely voluntary and despite the training manual's advice to interviewers to be cheerful at all times - "no one wants to be interviewed by an unsmiling person with a dreary monotonous voice". Although the response rate is 78%, the ONS says that only 2% of people approached refuse to take part in it.

Passengers travelling at night, when interviews are suspended, or on smaller, low volume routes also slip through the net.

The one thing the IPS has over other sources of data on immigration - such as the number of non-EU passengers passing through border control, new NHS registrations or new National Insurance numbers - is that it records how long migrants say they intend to stay in the country.

Graph How accurate are the official net migration figures?

But its major flaw, according to experts, is when it comes to measuring how many people are leaving the country.

IPS emigration estimates are based on interviews with just 2,000 people (who, the ONS point out, are found from interviews with about 400,000 interviews) - and there is currently no alternative source of data to measure them against.

This matters because the coalition government has promised to reduce net migration - the difference between those entering and leaving the country - to "tens of thousands" by 2015.


Home Secretary Theresa May hailed "the first significant falls in net migration since the 1990s" in her keynote speech to the Conservative Party conference.

What she failed to mention was that when that "significant fall", from 252,000 to 216,000, was announced, the margin of error was also revealed for the first time.

What happened to e-borders?

Tony Blair
  • Tony Blair launched the £1.2bn e-borders programme in 2003
  • It was meant to collect details from passenger lists of all people entering and leaving the UK so that they can be checked against security watch lists
  • All flights from outside the EU are now part of e-borders
  • Ports and railway stations are due to follow by 2014
  • EU flights are meant to be covered by 2015
  • But that will depend on reaching voluntary agreements with other nations - and solving commercial problems
  • The US firm handed a £750m contract by Labour to deliver e-borders, Raytheon, was fired by the coalition in 2010 for "extremely disappointing" performance
  • The company is seeking £500m in damages from the government
  • The e-borders contract was split in two with IBM and Serco given the job of getting a system in place at nine airports before the Olympics
  • The contract for the post-Olympics element of the programme - the biggest part of it - has yet to be awarded

This showed that the main source of these figures was only accurate to within plus or minus 35,000 people.

In other words, according to the ONS, the fall was not yet statistically significant.

This does not mean, of course, that net migration has not fallen, just that, according to some experts, the government's main method of measuring its progress is little better than a rough guess.

"It is very difficult to assess how well the government is progressing toward its target of reducing net-migration to the 'tens of thousands', or to evaluate the effects of specific policy changes," says Dr Martin Ruhs, Director of the Migration Observatory at the University of Oxford.

"In simple terms the government could miss the 'tens of thousands' target by many tens of thousands and still appear to have hit it - conversely the government could hit, or even exceed its target and still appear to have missed it."

The government denies that the IPS is a faulty instrument for measuring its progress on migration.

In a statement to the BBC, Immigration Minister Mark Harper said: "The International Passenger Survey already provides the ONS with a reliable method of measuring net migration.

"By 2015, we aim to reintroduce exit checks using the e-borders system, which will allow us to build an even more accurate picture of the number of people entering and leaving the country."

A brainchild of the Tony Blair era, when it seemed as if there was no problem that could not be solved by a multi-billion pound IT project, e-borders was meant to replace the old paper-based embarkation system, which was scrapped in the 1990s.

Since then departures from the UK have not been officially recorded.

So it is possible for migrants to enter on short-term visas and - unless they notify the authorities of their intention to stay longer or are really, really unlucky and are picked up in a Border Force raid - stay in the UK or leave the country years later without showing up in the official records.

It was one of the justifications Mr Blair made - and is still making - for the introduction of an identity card system.

E-borders which was primarily meant to improve security, when combined with a biometric identity card scheme, began collecting details of passenger and crews for inbound flights from outside the EU at nine airports in March.

The plan now is to extend it to ports and railway stations by 2014 and to passengers from within the EU by 2015.

But that will depend on persuading all EU countries to share passenger and crew list information - quite a number of them regard this as illegal under European free movement laws.

High hopes

And there are some, such as Keith Vaz and Sir Andrew Green, of think tank Migration Watch, who fear the project, which was meant to be up and running in time for the Olympics, may have stalled altogether.

"The government will rightly be held to account if they fail to achieve a steady and substantial reduction in net migration, whatever the technical details," said Sir Andrew.

"But it is time we were told more about the purpose and progress of the e-borders programme."

The statisticians at the ONS still have high hopes that e-borders will one day be able to provide reliable migration statistics.

But they say it will be 2018 at the earliest before they can even start incorporating data from the programme into their estimates - and there are no plans to replace the IPS as the main source of migration data.

So until the Home Office can be persuaded to come up with a different method - the men and women of the IPS will continue to put on their best smiles and try not to panic as they scan the arrivals halls of Britain's ports and airports.

And net migration statistics should continue to be taken with a major dose of salt.

Graph showing increase in migration

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  • rate this

    Comment number 594.

    Of course the number of immigrants coming into the country could be accurately measured, controlled, restricted to an intake of required skills and a manageable flow of refugees and genuine asylum seekers...The fact that it wasn't proves that the current chaos was politically intended and engineered - and not due to incompetence or unforeseen circumstances.

  • rate this

    Comment number 593.

    // Little_Old_Me
    .....that way we'll find out exactly how FEW foreigners are here compared to the "man in the street's" gut instinct of how many are here.

    Most African & Asian descended folk are British....not foreigners...//

    Know all that for a fact, do you? The fig.s might not be as you think. Most 'facts' believed or propagated by pro-immigration brigade are wrong. remember.

  • rate this

    Comment number 592.

    'Purely anecdotal of course, but it's not *that* easy to come and live in the UK'

    Apart from a few anomalies in the system regarding spouses etc I'd say it is *that* easy to come to the UK to live in comparison with lot's of other countries inc USA

    Hence why this is a preferred destination for so many immigrants and asylum seekers.

    A walk across London may change your view

  • rate this

    Comment number 591.

    I had a friend from America who finished her degree and wanted to live here with her boyfriend. She had a job and a home, but was unable to obtain a visa and had to leave. Her boyfriend was able to live with her in America despite being a jobless alcoholic.

    Purely anecdotal of course, but it's not *that* easy to come and live in the UK.

  • Comment number 590.

    This comment was removed because the moderators found it broke the house rules. Explain.

  • rate this

    Comment number 589.

    Its very strange how people can be so blinkered and don't view 2nd/3rd generation Indians/Africans as British.I have no problems with controlled immigration I'm just appaled at the level its got to. Our services strecthed,mass unemployment, integeration issues and growing resentment.Doing an Ostrich won't solve the problem, nor will shouting your rascist/right wing/left wing etc!

  • rate this

    Comment number 588.

    JPublic..Your rhetoric echoes those same idiots who ring up James Whale"

    As oppossed to your left-wing rants with no basis? You sure you jumped from that plane or were you pushed??

  • rate this

    Comment number 587.

    I'm glad to see the expression about calling "something a something" has been clarified by removing my posting. I hope you'll do the decent thing and remove your own now Tacky. If you had read it properly you would have noted that I was querying your usage of the expression. This discussion is about immigration not racism which you seem to have in spades - ooops.
    Immigration needs to be reduced.

  • rate this

    Comment number 586.

    Just a description of a bog standard democratic model seen in action every day across the world.
    Your words not mine.

  • rate this

    Comment number 585.

    580. "No, they came as violent invaders, with disastrous effects on the peoples and cultures already here. So, just like immigration now."

    Or, to put it another way, precisely nothing like immigration now.

    We are in no sense being "invaded"- what a ridiculous comparison!

    I daren't ask what exactly you think immigration has done to British culture that is so terrible.

  • rate this

    Comment number 584.

    Have you been to Birmingham/London/Manchester? Have you seen the areas with 8+ people living in a 2 bed house having on average of 6 children a family who do not (mostly) register the births?. For the uneducated/uninformed it is easier to pretend this does not happen in their little town. This whole article and comment section really can send ones pressure up. Maybe a revolution is just!!!

  • rate this

    Comment number 583.

    577. Little_Old_Me - Accurate figures will probably prove this. Unfortunately some of our fellow countrymen are unable to see Brits of African or Asian descent born here, raised here, paying tax here as Brits. Leaving in a shires county town I think many would be surprised by how many of the "middle class" are from that same group.

  • rate this

    Comment number 582.

    Can you quantify your last statement? I would be interested to know where you got your facts & figures from.

  • rate this

    Comment number 581.

    Really, seriously, POT and Kettle. Left wing GUFF!. Ghetto's have been created because of Essex and Kent daily mail readers. Oh please.

  • rate this

    Comment number 580.


    I don't think you know how quickly the Normans and Saxons integrated. I'm certain that you can't pin it down to a matter of years.//

    No, they came as violent invaders, with disastrous effects on the peoples and cultures already here. So, just like immigration now.

    And bear in mind, the previous invasions resulted in the mainstream Brits, who are apparently terrible...

  • rate this

    Comment number 579.

    This needs to be sorted out now before its to late ,

  • rate this

    Comment number 578.

    We are a small island and cannot cope. We have too few indiginous layabouts employed and rely on exploiting people who come here for a better life because we have screwed up their own country - what a mess

  • rate this

    Comment number 577.

    I for one certainly hope the Govt gets a system in place to create accurate counting, espcially of those leaving who aren't really counted under the present system......

    .....that way we'll find out exactly how FEW foreigners are here compared to the "man in the street's" gut instinct of how many are here.

    Most African & Asian descended folk are British....not foreigners...

  • rate this

    Comment number 576.

    Typical Right Wing reactiuonary un educated GUFF !

    Practice what you preach Takeley.

    Your rants could do with factualisation modification, oh yee of the wringing hands.

  • rate this

    Comment number 575.

    Sounds like incitement to riot to me. You want to watch that, you might get made an example of. =(


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