International Financial Law Prof Blog.
Still, the government’s default measure vastly underestimates the problem. The government considers people in default if they have made no payments in 360 days. A broader measure by Federal_Reserve_Governors_sealthe New York Federal Reserve—which accounts for all Americans with student loans—shows that roughly one in four borrowers are at least 90 days behind on a payment.
William Byrnes' Tax, Wealth, and Risk Intelligence 