Year Dollars 1997-01-01 230636 2002-01-01 1331346 2003-01-01 1091453 2004-01-01 2216876 2005-01-01 3017284 2006-01-01 2322142 2007-01-01 4125256 2008-01-01 6169760 2009-01-01 5561619 2010-01-01 9488401 2011-01-01 12278319 2012-01-01 12717275 2013-01-01 14568781 2014-01-01 21167624 2015-01-01 35648612 2016-01-01 16241155