The information requested falls within the responsibility of the UK Statistics Authority. I have asked the authority to reply.
Letter from Karen Dunnell, dated January 2009:
As National Statistician, I have been asked to respond to your questions concerning what estimate the Office for National Statistics has made of (a) the number of Polish persons living in the UK in 2007 and 2008, (b) the number of Polish persons who returned to Poland from the UK in 2008 and (c) how many Polish persons are currently living in the UK (249587).
The Office for National Statistics collects data on country of birth on the Annual Population Survey (APS) which covers residents of the UK. Estimates from the APS show that in 2007, 405,000 people living in the UK were born in Poland. This estimate has a margin of error of +/-26,000. No data are not yet available for 2008 or 2009.
The number of Polish persons who returned to Poland from the UK in 2008 is not yet available. The latest data for 2007 show that 18,000 UK residents who were born in Poland, migrated back to Poland. This estimate is based on the International Passenger Survey and excludes people who have been living in the UK for less than a year or who intend to return to Poland for less than a year.