The top 10 biggest U.S. Cities on the brink of Pension bankruptcy According to Business Insider, here are the top 10 U.S. cities whose pension obligations will soon collapse: (this article was originally published in 2010, so we have updated the "years" to reflect 2013 #1 Philadelphia - Unfunded liability of $9 billion, $16,696 per household, only 1 year before the pension accounts are empty #2