Loan defaults drain $37 billion from 401(k)s each year

http://money.cnn.com/2012/07/17/retirement/401k-loan-defaults/index.htm?iid=HP_LN

A large number of Americans are borrowing against their 401(k)s and having a hard time paying the loans back.
Defaults on 401(k) loans are draining retirement savings by as much as $37 billion a year, according to a study conducted by Robert Litan, a researcher at the Brookings Institution and Hal Singer, managing director of financial analysis firm Navigant Economics.