Year Dollars 1992-01-01 3273435 1997-01-01 4970984 2002-01-01 7093116 2003-01-01 9138748 2004-01-01 13002285 2005-01-01 16816038 2006-01-01 17703354 2007-01-01 17243474 2008-01-01 15410716 2009-01-01 12726599 2010-01-01 21790696 2011-01-01 19880707 2012-01-01 17016783 2013-01-01 20974691 2014-01-01 22249391 2015-01-01 23031561 2016-01-01 24573319