The WSJ details a startling jump in enrollment to a US student debt program that caps borrowers at paying 10% of their discretionary income per year and is then forgiven after 10 or 20 years.

Enrollment in the plans has surged nearly 40% in just six months, to include at least 1.3 million Americans owing around $72 billion, U.S. Education Department records show.

Some of the growth is due to users gaming the complicated system but it also speaks to the crushing debt loads many graduates are carrying.