Jeffrey Passel, a demographer at the Pew Hispanic Centre, estimates that the number of illegal immigrants in America fell by 500,000 between 2007 and 2008. Some left the country; others worked their way to legitimacy. Few were replaced. For the past three years, Mr Passel reckons, there has been more legal than illegal immigration—a reversal of the previous pattern. And even legal immigration may now be falling. HERE [1]