dave,
2014 is just one year. How many people have left the UK since EU borders opened? How many have arrived?

Oxford University Migration Observatory,

The accession of eight East European countries (A8 countries) to the EU in 2004 led to a significant increase in the inflow of EU citizens to the UK. The average annual Long-Term International Migration (LTIM) inflow of EU citizens (excluding British citizens) for 2004-2012 was around 170,000, compared to 67,000 during 1997-2003.
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LTIM estimates suggest that net migration of A8 citizens was 30,000 in 2012. During 2004-2012, LTIM data suggest that total net migration of A8 citizens was 423,000; however, the ONS has indicated that this is an underestimate.
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Results from the 2011 Census suggest that 2.7 million residents of the UK were born in other EU countries. About 1.1 million of those (42%) were born in countries which joined the EU in 2004 or afterwards.
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The number of A8 citizens working in the UK number was estimated at 723,000 in the third quarter of 2013 according to the Labour Force Survey (LFS).
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