Payments are based on a borrower's discretionary income, which is determined based on family size using the federal poverty guidelines. (vox.com)
I'm surprised that the calculator doesn't have a minimum family size of 14. (religion.blogs.cnn.com)
This was reinforced by important social trends, the reduction in average family size meant that many parents could devote more time to each of their children. (sciencedaily.com)