I'm a Danish student at Caltech, a few months ago I was reading a study from the statistics department that from every 100 Latin American students in the American superior studies system (colleges, universities) 62% return to their countries, 20% stays in the US, and the rest move to another country, most likely in Asia. 90% Europeans students return to their countries. While from every 100 Indian students, 82% stays in the US, but keep in mind that the US educational system receives 60000 approx just from India every year while the rest of the international students are just around 23000. Your tech work force is going to be replaced by indians in just 15 years at this rate, since most indians are getting into tech fields.