Year Percent 1993 0.76175 1994 1.04163 1995 0.9581 1996 0.8736 1997 1.04677 1998 1.06749 1999 1.28711 2000 1.37633 2001 1.50221 2002 1.66713 2003 1.74305 2004 1.69969 2005 1.89926 2006 1.85701 2007 1.99798 2008 2.09296 2009 2.20913 2010 1.70353 2011 1.6799 2012 1.89575 2013 1.9068 2014 1.95282 2015 2.05429 2016 2.13287 2017 2.0983