A BBC poll has been claimed to show millions of Bulgarians and Romanians intend to move to the UK, but is such a conclusion ever really valid?

"25% of Bulgarians want job in UK", read a Press Association story this morning. The Telegraph makes a marginally less audacious claim that "350,000 Bulgarians and Romanians" are looking for work in the UK, but are either of these assertions credible?

Survey-based immigration projections are notoriously unreliable - just last year the Sun splashed "EXCLUSIVE" across a story claiming "48% of Brits want to get out of the UK" - so why do news organisations from across the spectrum persist in giving such garbage prominence?

The fact that the BBC themselves lead with "No indication of huge Romanian-Bulgarian influx" should tell us all we need to know.

The Telegraph reach their figure by adding the proportions of Bulgarians and Romanians who said they were looking to work in the UK in 2013 or 2014, but drill down a little further into the poll results most of that figure said they would only migrate if they received a firm offer of work.

To equate a broad wish to migrate to the UK for a job with an imminent threat of immigration inundation is careless at best and actively misleading at worst.

If we apply the same conversion to the Sun's claim, 30m Britons should by now have upped sticks and headed overseas. In actual fact there were 352,000 emigrants in the year ending June 2012, giving us an exaggeration factor of 86.

Admittedly the distortion factor in Bulgaria is lower - recorded emigration rates of between 6% and 7% compare to figures of up to 50% reported in polls of the capital Sofia - but the overarching point remains the same; immigration polls are not to be trusted.

If any figures from the poll are to be treated as concrete signals of future migration, they are those concerning people who have begun making concrete plans to move, such as looking for accommodation.

In this case those are 1.2% and 0.4% for Bulgaria and Romania respectively, or a total of 117,240 in Telegraph money. The latest World Bank data puts the total number of Bulgarian and Romanian emigrants to the UK at 14,790, so while the requisite increase is by no means impossible, it would have to be dramatic to see these figures realised.

In addition to the issue of exaggeration, the BBC poll also found that the proportion of Bulgarians and Romanians looking for work elsewhere in the EU in 2014 is down on the same figure for 2013.

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