Year Dollars 1997-01-01 3906125 2002-01-01 7029955 2003-01-01 10697006 2004-01-01 9342851 2005-01-01 11759611 2006-01-01 10593526 2007-01-01 13906446 2008-01-01 13073404 2009-01-01 11270815 2010-01-01 15218389 2011-01-01 19147399 2012-01-01 19477247 2013-01-01 20676567 2014-01-01 19896269 2015-01-01 20311828 2016-01-01 13645482