Year Dollars 1992-01-01 6716923 1997-01-01 8664566 2002-01-01 16796139 2003-01-01 19930258 2004-01-01 19369953 2005-01-01 21018620 2006-01-01 23274520 2007-01-01 23150284 2008-01-01 31459428 2009-01-01 37092683 2010-01-01 35449124 2011-01-01 36992718 2012-01-01 35512118 2013-01-01 30074664 2014-01-01 28630102 2015-01-01 26419377 2016-01-01 33702240