Year Dollars 1997-01-01 249616 2002-01-01 1016092 2003-01-01 2054501 2004-01-01 707337 2005-01-01 1436656 2006-01-01 4434559 2007-01-01 8667085 2008-01-01 11297680 2009-01-01 12559167 2010-01-01 15616906 2011-01-01 21581178 2013-01-01 10548817 2014-01-01 15276391 2015-01-01 11532063 2016-01-01 4611821