Estimates of the number of families with tax credit awards, including information on overpayments by constituency, based on final family circumstances and incomes, for the years 2003-04, 2004-05, 2005-06 and 2006-07 are available in the HMRC publications “Child and Working Tax Credits Statistics. Finalised Annual Awards. Supplement on Payments. Geographical Analyses”, for each relevant year. These publications are available on the HMRC website at:
http://www.hmrc.gov.uk/stats/personal-tax-credits/cwtc-geog-stats.htm
Estimates for 2007-08 are not yet available.