Year Dollars 1992-01-01 6247740 1997-01-01 15636171 2002-01-01 14966936 2003-01-01 18671414 2004-01-01 21906518 2005-01-01 22629116 2006-01-01 34374076 2007-01-01 41934858 2008-01-01 41850028 2009-01-01 22109128 2010-01-01 35873364 2011-01-01 23332540 2012-01-01 24475529 2013-01-01 21691955 2014-01-01 23602547 2015-01-01 16290445 2016-01-01 28184323