Year Dollars 1997-01-01 41100446 2002-01-01 18771179 2003-01-01 21188683 2004-01-01 20288996 2005-01-01 29824576 2006-01-01 25636599 2007-01-01 32787721 2008-01-01 21138757 2009-01-01 19006606 2010-01-01 11936245 2011-01-01 12705113 2012-01-01 13131701 2013-01-01 15658786 2014-01-01 20520649 2015-01-01 23090200 2016-01-01 23037694