Year Dollars 1992-01-01 7409273 1997-01-01 4036421 2002-01-01 4868679 2003-01-01 10323554 2004-01-01 13006448 2005-01-01 20008837 2006-01-01 23663619 2007-01-01 25279806 2008-01-01 26826444 2009-01-01 17054550 2010-01-01 22437155 2011-01-01 21972955 2012-01-01 15623480 2013-01-01 17213534 2014-01-01 30582635 2015-01-01 42293415 2016-01-01 51535590