Largest population transfer on earth 1990-2010 has been Mexico to United States. 12.7 million Mexicans reside in US as of 2017-UN International Migration Reports

.
2016, "International Migration Report 2015," by the United Nations, Dept. of Economic and Social Affairs 

For two decades, 1990-2010, the largest population transfer on earth remained Mexico to the United States:

*1990-2000: US added 5 million Mexicans, 500,000 annually:

(p. 21-23, pdf): "Mexico to USA was the largest bilateral migration corridor in the world, with an annual average of nearly 500,000 migrants born in Mexico being added to the population of the United States of America from 1990 to 2000. Fig. I6" [5 million over ten years] UN chart, page 22, pdf

*2000-2010: US added 2.4 million Mexicans, 240,000 annually:

page 23, pdf: "During the period from 2000 to 2010...Mexico-USA continued to be the corridor with the largest gain--on average, around 240,000 additional migrants per year." 
.............. 

An estimated 12.7 million Mexicans reside in the US as of 2017, up from 9.4 million in 2000:

2017, "International Migration Report," United Nations Dept. of Economic and Social Affairs

page 14: "Migratory movements between pairs of countries are referred to as “bilateral corridors”. The largest bilateral corridor in 2017 was that between Mexico and the United States of America. The latter hosted 98 per cent of all Mexican-born individuals (12.7 million) residing abroad (figure 8)."

.................
Comment: Via its open borders policies, the US political class continues to be the safety valve for tyrannical and incompetent governments around the world including Mexico. Such governments have no incentive to change as long as US taxpayers are offered up as global slaves to anyone who walks by.



......................