Year Percent 2000 5.32611 2001 6.78367 2002 6.21535 2003 4.69668 2004 3.78074 2005 3.1665 2006 2.79267 2007 2.33486 2008 1.7701 2009 1.96904 2010 3.20103 2011 3.74927 2012 4.05761 2013 4.41021 2014 4.06674 2015 3.24148 2016 2.5524 2017 2.0776