According to census data released earlier this month, the number of illegal immigrants in the United States shows significant decline after more than a decade of increases, with an estimated 11.1 million undocumented individuals residing in the country in 2011 compared with a peak figure of 12 million in 2007.

Following record highs of illegal migration between the mid-1990s and early 2000s, the new statistics, which are derived primarily from the Census Bureau’s Current Population Survey through March 2011, indicate that economic decline, an aging population, and record numbers of immigrants from Asian countries have supplanted the Mexico-based migration traditionally associated with illegal immigration. In fact, new figures also show that fewer undocumented Mexican immigrants are entering the United States, with many of those who are already inside the country electing to return to Mexico.