The annual inflow of unauthorized immigrants to the U.S. has declined sharply in the recent years. During the first half of the decade, an average of about 850,000 new unauthorized immigrants entered each year. Between March 2005 and March 2007, the inflow of unauthorized immigrants fell to an average of roughly 550,000. And the decline continued in recent years; a yearly average of 300,000 unauthorized immigrants entered the U.S. from March 2007 to March 2009. This means the annual inflow of unauthorized immigrants to the U.S. was nearly two-thirds smaller from 2007 to 2009 than it had been from early this decade. This decline contributed to an overall 8% reduction in the unauthorized immigrant population, which fell to 11.1 million in 2009 from 12 million in 2007, the first significant reversal in the growth of this population over the past two decades. Read More

Russell Heimlich  is a former web developer at Pew Research Center.