FACTBOX: Poles leaving Britain: Some key figures

(Reuters) - Some of the Polish workers who moved to Britain after their country joined the European Union in 2004 are returning home as economic conditions there improve while a slowdown in Britain gathers pace.

Poles are the biggest group of workers in Britain from the eight former communist countries which joined the EU four years ago. Migration groups say unregistered migrants mean the total number of "accession eight" workers in Britain could be as much as 50 percent higher than official figures.

Here are some key facts on Polish workers and Poland:

* An estimated 2 million workers have left Poland for Britain and other Western countries since 2004. 812,000 workers from the eight new EU entrants are registered under Britain's work registration scheme, and 70 percent are Polish. Slovaks make up the second largest group at 12 percent.

* There are 220,545 registered Polish factory workers in Britain; 580 registered Polish plumbers, heating and ventilation engineers; five registered Polish police officers.

* Sixty percent of work registration applicants have said they wanted to stay in Britain for three months or less. There was a 17 percent drop in applications to the scheme in the second half of 2007 from a year earlier.

* Out of 24,850 applicants for tax-funded welfare in Britain from the eight new entrants, 12,362 were from Poland.

* In December 2003, 40,000 passengers flew between British and Polish airports. In December 2007, that number was 385,000. A one-way ticket on easyjet from Warsaw to London costs 75 pounds.

* Of the Poles who have returned home from Britain, 66 percent said they made the right decision.

* Poland has a population of 38.5 million and an average monthly wage of 702 pounds sterling. Britain has a population of 60 million and an average monthly wage of 2,250 pounds.

* Gross Domestic Product per head in Poland is 55 percent of the European Union average in purchasing power standards. In Britain, it is 115 percent of the average.

* The zloty has appreciated 46 percent against the pound since Poland joined the EU.

* Poland's unemployment rate now stands at 10.5 percent, compared with 19 percent in May 2004. An estimated 600,000 jobs remain unfilled in Poland because of a labor shortage.

* 207,000 Britons left their country in 2006.