Not sure what you are getting at. Goldman Sachs and the other investment houses have some good reports on this issue as well as economic criticism of the Republican immigration plan. The problems started with how many femaile children your grandmother, mother or your wife had (assuming you are at the average). Birth rate has been going down, now there are fewer and fewer women of fertile child bearing age or just old enough to have 1 child and not 3 or 4. So fewer young working people to support lots of old people-- pay for nursing care, care housing, and medical expenses. Go read the economists and guys from the investment banks-- like the article from Goldman Sachs.