$15 trillion national debt

The total national debt just passed $15 trillion on 11/15/2011.  It first passed $10 trillion on 9/30/2008, only a little more than 3 years ago.

I think a better measure is debt held by the public. It first exceeded $5 trillion on 3/1/2007 and $10 trillion on 8/31/2011.  It will exceed $15 trillion by 9/30/2016.