The U.S. has approved more than $42 billion in federal student loan debt forgiveness for more than 615,000 borrowers over the past 18 months. It’s part of a program aimed at getting more people to work in public service jobs. The Public Service Loan Forgiveness program is open to teachers, librarians, nurses, public interest lawyers, military members and other public workers. It cancels a borrower’s remaining student debt after 10 years of public interest work, or 120 monthly payments. Stringent rules meant that many applicants were rejected, but a recent waiver made it easier for people to apply and get their debt forgiven.