Year Dollars 1992-01-01 3975874 1997-01-01 6927405 2002-01-01 17966306 2003-01-01 18820867 2004-01-01 25474668 2005-01-01 13250855 2006-01-01 14492225 2007-01-01 12996990 2008-01-01 20215869 2009-01-01 36215776 2010-01-01 36358801 2011-01-01 33653809 2012-01-01 30051679 2013-01-01 25968714 2014-01-01 19708607 2015-01-01 19325153 2016-01-01 22154766