Source: "Six degrees and separation"
Some breakdowns on American immigration - for 2015, the last year with data, when looking at the 1 million people given green cards (i.e. permanent resident status), about half or 50% were immediate relatives of citizens (the so-called 'chain migrants'). Then 20% more got their cards because of preferences given to other family members. Then about 15% were sponsored by companies and about 10% got in as refugees. That left about 5% who got in through our lottery system. However, what stands out is how many of these green card holders have college degrees. That percent was about 27% in the late 80's - it has risen to 50% in 2015. Immigrants were more educated than the average American in 26 different states.
Some background on a points-based immigration system. From the article: "In 1967 Canada became the first country to introduce a points system for immigration; Canada and Australia now both give priority to would-be migrants with degrees, work experience and fluent English (and, in Canada, French). Some of the president’s advisers think this more hard-headed system is better than America’s family-centered approach. The doomed immigration bill from 2013 that died in the House of Representatives also reflected widespread enthusiasm for a points-based system. Two things ought to temper this enthusiasm. First, Canada and Australia have concluded that pure points systems do not work well. A surprisingly high share of the people admitted this way ended up unemployed. Both countries have since changed their immigration criteria so that applicants who have job offers in their pockets may jump the queue. Second, migrants who move to America to join family members have become much better educated."
A charity, Upwardly Global, helps highly educated immigrants translate their foreign degrees into American equivalents.