Year Dollars 1992-01-01 20759268 1997-01-01 14560180 2002-01-01 4031397 2003-01-01 7605562 2004-01-01 3362466 2005-01-01 2534250 2006-01-01 6960107 2007-01-01 11709496 2008-01-01 17347012 2009-01-01 25826004 2010-01-01 11266942 2011-01-01 20596158 2013-01-01 13198117 2014-01-01 9114312 2015-01-01 23425048 2016-01-01 17785693