Year Percent 1992 2.60601 1993 2.73079 1994 2.42801 1995 1.7615 1996 1.80616 1997 1.45707 1998 1.29761 1999 1.10301 2000 0.97259 2001 0.88327 2002 0.77205 2003 1.05551 2004 1.14179 2005 1.03108 2006 0.76339 2007 0.60887 2008 0.41861 2009 0.64069 2010 1.08687 2011 1.48281 2012 1.68314 2013 1.5713 2014 1.35759 2015 1.32279 2016 1.28182 2017 1.06247