Immigration has increased the population of the UK since the 1980s, though Eastern European migrants in particular have been leaving since the recession. As well as swelling the numbers when they arrive, immigrants are more likely than others to be in their fertile years and so have a significant effect on the birth rate. In 2009 almost 25% of births here were to mothers born outside the UK, even though only 8% of the population are not of white British descent. Immigrants come to the UK because of pull and push factors.
