Year Percent 1992 4.29358 1993 4.44615 1994 4.44864 1995 3.58609 1996 3.5187 1997 3.01769 1998 2.26681 1999 1.55123 2000 1.11041 2001 0.84696 2002 0.98169 2003 1.16567 2004 1.13179 2005 1.05359 2006 1.09132 2007 1.21975 2008 1.54275 2009 3.30865 2010 4.8298 2011 5.35579 2012 5.41478 2013 4.77932 2014 4.04283 2015 3.31824 2016 2.69402 2017 2.00682