Research conducted by the Migration Policy Institute for the Equality and Human Rights Commission suggests that, between May 2004 and September 2009, 1.5 million workers migrated from the new EU member states to the UK, but that many have returned home, with the result that the number of nationals of the new member states in the UK increased by some 700,000 over the same period. Migration from Poland in particular has become temporary and circular in nature. In 2009, for the first time since the enlargement, more nationals of the eight Central and Eastern European states that joined the EU in 2004 left the UK than arrived. Research commissioned by the Regeneration and Economic Development Analysis Expert Panel suggested migrant workers leaving the UK due to the recession are likely to return in the future and cited evidence of "strong links between initial temporary migration and intended permanent migration".