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We have seen a significant decline in illegal immigration from Mexico to the United States and it's clear that the Border enforcement build up has been a big reason why that decline has been as sharp as it has been, our estimates suggest that the number of successful illegal entries has fallen from extremely high numbers – more than 3 million annually up to the mid-2000s– to much, much smaller numbers, about 250,000 last year. Keep in mind that these numbers do not represent individuals who came to stay in the United States – these are the total number of illegal border crossings.